# bitlvl

> Fast, private developer tools: binary and hex converters, bitwise and subnet calculators, Base64, hashes, JWT, timestamps, cron, chmod. All in your browser.

bitlvl is a collection of free, client-side developer tools at https://bitlvl.com. Every tool runs entirely in the browser; no input is sent to a server. Each tool page explains the underlying concept, shows worked examples and answers common questions.

## Numbers & bits

Convert between bases, flip bits, and see how machines store numbers. Index: https://bitlvl.com/numbers/

- [Base converter](https://bitlvl.com/numbers/base-converter/): Convert numbers between binary, decimal, hexadecimal and octal with the step-by-step working shown. Handles big numbers, prefixes and negatives. Free.
- [Binary to decimal converter](https://bitlvl.com/numbers/binary-to-decimal/): Convert binary to decimal instantly and see the working: each 1 bit multiplied by its power of two, added up. Also shows hex and octal. Free, no sign-up.
- [Decimal to binary converter](https://bitlvl.com/numbers/decimal-to-binary/): Decimal to binary calculator that shows every step of the repeated division by two. Handles large numbers and negatives, and shows hex and octal too. Free, no sign-up.
- [Hex to decimal converter](https://bitlvl.com/numbers/hex-to-decimal/): Convert hexadecimal to decimal with the powers of sixteen shown. Accepts 0x prefixes and long values such as hashes and addresses. Also gives binary and octal. Free.
- [Decimal to hex converter](https://bitlvl.com/numbers/decimal-to-hex/): Convert a decimal number to hexadecimal and see the repeated division by 16. Handles big numbers, shows binary and octal, adds the 0x prefix if you want it. Free.
- [Hex to binary converter](https://bitlvl.com/numbers/hex-to-binary/): Convert hexadecimal to binary: every hex digit becomes four bits. Shows grouped output, decimal and octal, and a hex-to-binary table. Free, in your browser.
- [Binary to hex converter](https://bitlvl.com/numbers/binary-to-hex/): Convert binary to hexadecimal by grouping bits in fours. Accepts spaces and 0b prefixes, shows decimal and octal, and explains the method. Free, no tracking.
- [Bitwise calculator](https://bitlvl.com/numbers/bitwise-calculator/): Bitwise AND, OR, XOR, NOT, shifts and rotates on 8, 16, 32 or 64-bit values. Enter hex, decimal or binary and see every bit of the result. Free.
- [Bitmask calculator](https://bitlvl.com/numbers/bitmask-calculator/): Build a bitmask from bit positions (0, 3, 5-7) or paste a mask to see which bits are set. Name your flags and get ready-to-paste constants. Free.
- [Two's complement converter](https://bitlvl.com/numbers/twos-complement/): Convert decimal, binary and hex in two's complement at 8–64 bits. See signed and unsigned readings, range limits and the invert-and-add-one steps.
- [IEEE 754 float visualizer](https://bitlvl.com/numbers/ieee-754-float/): See how a float32 or float64 stores a number: sign, exponent, mantissa, hex bits and the exact value after rounding. Explains why 0.1 + 0.2 ≠ 0.3.
- [Byte & data size converter](https://bitlvl.com/numbers/byte-converter/): Convert bits, bytes, kB/MB/GB and KiB/MiB/GiB, see the 1000 vs 1024 difference, and get transfer time at any link speed. Free, in your browser.
- [CRC & checksum calculator](https://bitlvl.com/numbers/crc-calculator/): Compute CRC-32, CRC-32C, CRC-16 (MODBUS, CCITT, XMODEM, X-25…), CRC-8, CRC-64 and Adler-32 / Fletcher checksums of text, hex or a file, with each variant's parameters.
- [Endianness converter](https://bitlvl.com/numbers/endianness-converter/): Swap the byte order of a 16, 32 or 64-bit value and see how it sits in memory in big-endian (network order) and little-endian (x86, ARM) form, with swap code.
- [Gray code, BCD & popcount](https://bitlvl.com/numbers/gray-code-converter/): Convert binary to Gray code and back, pack numbers as BCD, and get the Hamming weight (popcount), parity and bit length, with the one-line formulas and a sequence table.
- [Roman numeral converter](https://bitlvl.com/numbers/roman-numerals/): Convert a number to Roman numerals or a Roman numeral to a number, with the subtraction rules explained, validation of invalid forms, and a table of years and values.
- [Number to words](https://bitlvl.com/numbers/number-to-words/): Write any number in words: 39 900 is thirty-nine thousand nine hundred. Up to quintillions, with the cheque and invoice form (and 56/100 dollars), capitals and negatives.
- [C struct layout & bit-field visualizer](https://bitlvl.com/numbers/struct-layout/): See the memory layout of any C struct: offsets, padding, alignment and sizeof for x86-64, ARM64, i386 and MSVC, bit-field packing, a reorder that shrinks it, hex decode.
- [Integer overflow & arithmetic calculator](https://bitlvl.com/numbers/integer-overflow/): Evaluate integer expressions in a fixed-width type with C/C++, Rust, Go, Java or JavaScript rules: wraparound, undefined behaviour, promotion, unsigned conversion, shift.

## Networking

Subnets, prefixes and address maths for IPv4 and IPv6. Index: https://bitlvl.com/networking/

- [Subnet calculator](https://bitlvl.com/networking/subnet-calculator/): IPv4 subnet calculator: network, broadcast, usable range, wildcard mask and host count from a /prefix or netmask, with the mask in binary and subnet splitting.
- [IPv6 calculator](https://bitlvl.com/networking/ipv6-calculator/): Expand and compress IPv6 addresses (RFC 5952), get the range of any prefix, the address type, EUI-64 MAC recovery and the ip6.arpa reverse DNS name.
- [IP address ⇄ integer](https://bitlvl.com/networking/ip-to-integer/): Convert an IPv4 address to its 32-bit integer, hex, binary and octal forms, or a number back to a dotted address. Matches inet_aton and ip2long.
- [IP to hex converter](https://bitlvl.com/networking/ip-to-hex/): Convert an IPv4 address to hexadecimal (192.168.1.1 = 0xC0A80101, C0.A8.01.01) and hex back to a dotted address. Per-octet breakdown, decimal and binary too.
- [IP to binary converter](https://bitlvl.com/networking/ip-to-binary/): Convert an IPv4 address to binary, octet by octet (192.168.1.1 = 11000000.10101000.00000001.00000001), and binary back to a dotted address. Hex and decimal too.
- [MAC address lookup & formatter](https://bitlvl.com/networking/mac-address-lookup/): Look up the vendor of a MAC address from its OUI, detect randomised and multicast addresses, convert between notations, and derive the EUI-64 and IPv6 link-local address.
- [DNS lookup & mail checker](https://bitlvl.com/networking/dns-lookup/): Query any DNS record from Cloudflare and Google at once, compare answers to check propagation, follow the SPF include chain against the 10-lookup limit, check DMARC.
- [Port number reference](https://bitlvl.com/networking/port-numbers/): Searchable list of well-known and commonly seen TCP/UDP ports: 22 SSH, 53 DNS, 443 HTTPS, 3306 MySQL, 5432 PostgreSQL, 6379 Redis and more, with which never to expose.
- [DNS record explainer](https://bitlvl.com/networking/dns-record-explainer/): Paste dig output or zone-file lines and get each record explained: MX, SRV, SOA, CAA fields, plus full checks of SPF (lookup count), DMARC (policy) and DKIM keys.
- [Packet decoder](https://bitlvl.com/networking/packet-decoder/): Decode packet hex from tcpdump or Wireshark, or open a pcap/pcapng, in your browser: Ethernet, VLAN, ARP, IPv4/6, TCP, UDP, ICMP, DNS, DHCP, TLS, checksums verified.
- [CIDR aggregator & splitter](https://bitlvl.com/networking/cidr-aggregator/): Paste IPv4/IPv6 addresses, CIDR blocks and ranges and get the fewest prefixes covering them. Subtract exclusions, split blocks, export for nftables, iptables, Cisco.
- [Reverse DNS generator](https://bitlvl.com/networking/reverse-dns-generator/): Get the reverse DNS name of any IPv4 or IPv6 address, the in-addr.arpa or ip6.arpa zone for a prefix (including RFC 2317), and bulk PTR records for a whole block.
- [User-agent parser](https://bitlvl.com/networking/user-agent-parser/): Paste a User-Agent string to see the browser, engine, OS and device, and whether it is a search-engine, AI crawler or scraper bot (Googlebot, GPTBot, ClaudeBot, curl…).

## Encoding

Move text and bytes between the forms protocols expect. Index: https://bitlvl.com/encoding/

- [Base64 encode / decode](https://bitlvl.com/encoding/base64/): Encode text or files to Base64 and decode Base64 to text, hex or a file. Standard and URL-safe alphabets, missing padding, data: URLs. Nothing is uploaded.
- [URL encode / decode](https://bitlvl.com/encoding/url-encode/): URL-encode or decode text with the right rules for a query value, a whole URL or form data, and parse a full URL into its parts and parameters. Free.
- [Text ⇄ binary / hex / ASCII](https://bitlvl.com/encoding/text-to-binary/): Convert text to binary, hex, decimal or octal bytes (UTF-8) and back. Shows each character's code point and bytes. Handles emoji and accents.
- [Hex viewer](https://bitlvl.com/encoding/hex-viewer/): View any file or text as a hex dump with offsets, hex bytes and ASCII, like xxd or hexdump -C. Detects the file type from magic bytes. Files stay local.
- [Color converter & contrast checker](https://bitlvl.com/encoding/color-converter/): Convert any CSS colour between hex, rgb(), hsl(), hwb(), oklab() and oklch(), find the nearest named colour and check WCAG contrast of two colours. In your browser.
- [JSON formatter & validator](https://bitlvl.com/encoding/json-formatter/): Format, minify and validate JSON with the exact line and column of any error and a fix hint. Lenient mode accepts comments and trailing commas. Sort keys, JSON ⇄ YAML.
- [Unicode inspector](https://bitlvl.com/encoding/unicode-inspector/): See every character in a string with its code point, name, block and UTF-8/UTF-16 bytes. Finds zero-width and invisible characters, homoglyphs and NFC/NFD differences.
- [Text cleaner — invisible characters](https://bitlvl.com/encoding/text-cleaner/): See and remove every hidden character in text pasted from ChatGPT, Claude, web pages or PDFs: zero-width spaces, tag-character watermarks, bidi overrides, NBSP, BOM.
- [Punycode / IDN converter](https://bitlvl.com/encoding/punycode-converter/): Convert internationalised domain names (ü, ć, 日本語, кириллица) to their xn-- Punycode form and back, with per-label breakdown and homograph warnings.
- [HTML entity encoder / decoder](https://bitlvl.com/encoding/html-entities/): Encode text to HTML entities (named like é or numeric like é) and decode them back. Includes a searchable table of every HTML5 named character reference.
- [String escape tool](https://bitlvl.com/encoding/string-escape/): Escape a string for where it is going: JSON, POSIX shell, SQL literals, regex, C/Go/Rust strings, CSV, HTML, XML, YAML, Java properties, URL and Base64. Unescape too.
- [QR code generator](https://bitlvl.com/encoding/qr-code-generator/): Generate QR codes for URLs, text, Wi-Fi, contact cards, email and phone numbers with error-correction level, size and colours. Download SVG or PNG. Built in your browser.
- [Morse code translator](https://bitlvl.com/encoding/morse-code/): Translate text to International Morse code and back, play it as audio at a chosen speed, and see the full letter, number, punctuation and prosign table.

## Hashes & tokens

Digest, sign, decode and inspect, without sending anything anywhere. Index: https://bitlvl.com/security/

- [Hash generator](https://bitlvl.com/security/hash-generator/): Compute MD5, SHA-1, SHA-256, SHA-384 and SHA-512 of text or a file, as hex or Base64, with optional HMAC key and checksum comparison. Nothing is uploaded.
- [JWT decoder](https://bitlvl.com/security/jwt-decoder/): Paste a JWT to see its header, payload and signature, with expiry explained and optional HS256/384/512 verification. The token never leaves your browser.
- [UUID & ULID generator](https://bitlvl.com/security/uuid-generator/): Generate UUID v4, time-ordered UUID v7 or ULIDs, one or a thousand at a time, and decode any UUID to see its version and timestamp. Secure random source.
- [Password & passphrase generator](https://bitlvl.com/security/password-generator/): Generate strong random passwords or memorable passphrases from a 6,000-word list, with entropy in bits and time-to-crack per attack type. Rates your own password too.
- [bcrypt, Argon2 & scrypt hasher](https://bitlvl.com/security/password-hash/): Generate bcrypt, Argon2id, scrypt or PBKDF2 password hashes with chosen cost parameters, or paste a hash and a password to check they match. Pure JavaScript, verified.
- [TOTP / 2FA code generator](https://bitlvl.com/security/totp-generator/): Generate time-based one-time passwords (RFC 6238) from a Base32 secret or otpauth:// URI, plus a QR code to scan into an authenticator app. SHA-256/512, 8 digits, HOTP.
- [SSL certificate & CSR decoder](https://bitlvl.com/security/ssl-certificate-decoder/): Decode an X.509 certificate, CSR or public key: subject, issuer, validity, SAN list, key type and size, signature algorithm, extensions and fingerprints. Chains too.
- [SSH key fingerprint & converter](https://bitlvl.com/security/ssh-key-fingerprint/): Paste an OpenSSH public key to get its SHA256 and MD5 fingerprints, key type and size, convert between OpenSSH and PEM, and build authorized_keys lines with options.
- [HTTP security headers & CSP analyzer](https://bitlvl.com/security/http-headers-analyzer/): Paste curl -I output or a Content-Security-Policy. Get a grade, every header explained, what is missing, and a CSP check for unsafe-inline, wildcards and bypass hosts.
- [Webhook signature verifier](https://bitlvl.com/security/webhook-signature-verifier/): Paste a webhook body, signature header and secret to check the HMAC signature, with the exact recipe for GitHub, Stripe, Slack, Shopify, Twilio, Svix and generic schemes.
- [Random bytes & token generator](https://bitlvl.com/security/random-generator/): Generate cryptographically secure random bytes as hex, Base64, Base64URL or Base32, API keys with a prefix, unbiased random integers, dice rolls and UUIDs.

## Time

Timestamps and schedules, in any time zone. Index: https://bitlvl.com/time/

- [Unix timestamp converter](https://bitlvl.com/time/unix-timestamp/): Convert a Unix timestamp (s, ms, µs or ns, detected automatically) to a date in any time zone, or a date to epoch time. Live current timestamp.
- [Cron expression explainer](https://bitlvl.com/time/cron-explainer/): Paste a cron expression and read it in plain English with the next 10 run times in any time zone. Covers ranges, steps, lists, names and @macros.
- [Time zone converter & meeting planner](https://bitlvl.com/time/time-zone-converter/): Convert a date and time between zones and compare up to eight zones on a 24-hour grid to find a meeting slot. Uses real IANA rules, so DST is right for any date.
- [Date calculator](https://bitlvl.com/time/date-calculator/): Exact time between two dates in years, months, days, weeks, hours and business days, or add and subtract years, months, weeks, days or working days from a date.
- [Duration converter](https://bitlvl.com/time/duration-converter/): Convert durations between seconds, milliseconds, minutes, hours, days, clock notation (1:30:00), human text (1h 30m) and ISO 8601 (PT1H30M). Explains the ISO format.
- [systemd timer OnCalendar explainer](https://bitlvl.com/time/systemd-timer-calendar/): Understand systemd timer OnCalendar= expressions in plain English with the next runs, convert cron lines to OnCalendar, and get a complete .timer and .service template.

## Unix

Permissions and the other bits you type into a shell. Index: https://bitlvl.com/unix/

- [chmod calculator](https://bitlvl.com/unix/chmod-calculator/): Tick read, write and execute for owner, group and others and get the chmod command in octal and rwx form, with setuid, setgid and sticky explained.
- [umask calculator](https://bitlvl.com/unix/umask-calculator/): Enter a umask (022, 077, 002) and see the permissions new files and directories get, or pick the permissions you want and get the umask. Where to set it for services.
- [ls -l and stat explainer](https://bitlvl.com/unix/ls-stat-explainer/): Paste a line from ls -l or the output of stat and see what each field means: file type, permission bits, link count, owner, size, timestamps, inode and the . + @ markers.
- [Exit code reference](https://bitlvl.com/unix/exit-codes/): What a process exit code means: 0 success, 1 and 2 errors, 126 not executable, 127 not found, 128+n killed by signal n (137 OOM, 139 segfault, 143 SIGTERM), 255.
- [Linux signal reference](https://bitlvl.com/unix/signals/): Complete list of Linux signals with numbers, names, default actions and what sends them: SIGHUP 1, SIGINT 2, SIGKILL 9, SIGSEGV 11, SIGTERM 15 and the rest, exit codes.
- [Cron ⇄ systemd timer converter](https://bitlvl.com/unix/cron-to-systemd/): Convert a crontab entry into a ready-to-install systemd .timer and .service pair with Persistent=, logging and sandboxing, or an OnCalendar expression back to cron.
- [Diff tool](https://bitlvl.com/unix/diff-tool/): Compare two texts side by side with added and removed lines highlighted, character-level changes within lines, and a unified diff you can save as a .patch. No upload.
- [Regex tester](https://bitlvl.com/unix/regex-tester/): Test a regular expression against text with matches highlighted as you type, capture groups listed, a replace preview and a token-by-token explanation of the pattern.
- [nginx location tester](https://bitlvl.com/unix/nginx-location-tester/): Paste an nginx config and a URL: which server and location block win, the match order (=, ^~, regex, prefix) and the resulting rewrite, try_files or proxy_pass URI.
- [EXPLAIN plan visualizer](https://bitlvl.com/unix/explain-visualizer/): Paste EXPLAIN (ANALYZE, BUFFERS) output as text or JSON, or a MySQL EXPLAIN ANALYZE tree: where the time goes, estimates vs actual, spills, missing indexes, with fixes.
- [SQL formatter](https://bitlvl.com/unix/sql-formatter/): Format SQL in your browser: one clause per line, indented subqueries, CTEs, CASE and JOINs, upper or lower keywords, leading or trailing commas. Or minify to one line.

## Play

Puzzles and games about bits: a daily register puzzle, hex picross, and a logic-gate lab. Index: https://bitlvl.com/play/

- [Bit Flip — daily register puzzle](https://bitlvl.com/play/bit-flip/): A daily puzzle about bits: transform the start register into the target with shift, rotate, NOT, increment and one flippable bit, in as few moves as you can.
- [Bit Picross — hex nonogram](https://bitlvl.com/play/bit-picross/): A picross / nonogram where each finished row shows its hex value. Daily 8×8 and 16×16 pixel pictures solvable by logic alone, practice mode, and a timed hex-decode race.
- [Gate Lab — build logic circuits](https://bitlvl.com/play/gate-lab/): Build circuits from logic gates in your browser and check them against a truth table: NAND-only logic, XOR, half and full adders, multiplexer, 2-bit adder. Live sim.

## Reference

Tables and cheat sheets to keep open in a tab or print. Index: https://bitlvl.com/reference/

- [HTTP status codes](https://bitlvl.com/reference/http-status-codes/): All HTTP status codes 100–511 plus Cloudflare 520–530, each with its meaning and the real situation that produces it: 301 vs 302, 401 vs 403, 502 vs 504, 429, 422.
- [ASCII table](https://bitlvl.com/reference/ascii-table/): The full ASCII table: every character 0–127 in decimal, hex, octal and binary, with control-character names, Ctrl keys, HTML entities and URL encoding.
- [Bitwise tricks cheat sheet](https://bitlvl.com/reference/bitwise-cheat-sheet/): One printable page of bit tricks: test, set, clear and toggle bits, power-of-two checks, lowest set bit, alignment rounding, popcount, masks and the operator table.
- [chmod & permissions cheat sheet](https://bitlvl.com/reference/chmod-cheat-sheet/): Printable chmod reference: the rwx/octal table, common modes, symbolic syntax, setuid/setgid/sticky, umask, chown, safe recursive changes, find -perm and ACL basics.
- [Cron cheat sheet](https://bitlvl.com/reference/cron-cheat-sheet/): Printable crontab reference: field order, @daily-style strings, 20 ready-made schedules, PATH and % gotchas, locking with flock, logging and the crontab commands.
- [Subnet cheat sheet](https://bitlvl.com/reference/subnet-cheat-sheet/): Printable subnetting reference: every IPv4 prefix with mask, wildcard and host counts; private, link-local and CGNAT ranges; IPv6 prefixes and address types.
- [Base64 & encodings cheat sheet](https://bitlvl.com/reference/base64-cheat-sheet/): Printable Base64 reference: the alphabet table, how 3 bytes become 4 characters, padding, URL-safe and Base32 variants, and encode/decode commands per language.
- [Regex cheat sheet](https://bitlvl.com/reference/regex-cheat-sheet/): Printable regex reference: anchors, classes, quantifiers, groups, backreferences, lookarounds, flags, replacement syntax, common patterns and flavour differences.

## Port reference

One page per well-known port (163 pages): what runs on it, whether it is encrypted, whether it should be open, how to check and firewall it. Index: https://bitlvl.com/networking/port-numbers/

- [Port 1 (tcpmux)](https://bitlvl.com/networking/port-numbers/1/)
- [Port 7 (echo)](https://bitlvl.com/networking/port-numbers/7/)
- [Port 9 (discard / Wake-on-LAN)](https://bitlvl.com/networking/port-numbers/9/)
- [Port 13 (daytime)](https://bitlvl.com/networking/port-numbers/13/)
- [Port 20 (FTP data)](https://bitlvl.com/networking/port-numbers/20/)
- [Port 21 (FTP)](https://bitlvl.com/networking/port-numbers/21/)
- [Port 22 (SSH)](https://bitlvl.com/networking/port-numbers/22/)
- [Port 23 (Telnet)](https://bitlvl.com/networking/port-numbers/23/)
- [Port 25 (SMTP)](https://bitlvl.com/networking/port-numbers/25/)
- [Port 37 (time)](https://bitlvl.com/networking/port-numbers/37/)
- [Port 43 (WHOIS)](https://bitlvl.com/networking/port-numbers/43/)
- [Port 49 (TACACS+)](https://bitlvl.com/networking/port-numbers/49/)
- [Port 53 (DNS)](https://bitlvl.com/networking/port-numbers/53/)
- [Port 67 (DHCP server)](https://bitlvl.com/networking/port-numbers/67/)
- [Port 68 (DHCP client)](https://bitlvl.com/networking/port-numbers/68/)
- [Port 69 (TFTP)](https://bitlvl.com/networking/port-numbers/69/)
- [Port 70 (Gopher)](https://bitlvl.com/networking/port-numbers/70/)
- [Port 79 (finger)](https://bitlvl.com/networking/port-numbers/79/)
- [Port 80 (HTTP)](https://bitlvl.com/networking/port-numbers/80/)
- [Port 88 (Kerberos)](https://bitlvl.com/networking/port-numbers/88/)
- [Port 110 (POP3)](https://bitlvl.com/networking/port-numbers/110/)
- [Port 111 (rpcbind / portmapper)](https://bitlvl.com/networking/port-numbers/111/)
- [Port 113 (ident)](https://bitlvl.com/networking/port-numbers/113/)
- [Port 119 (NNTP)](https://bitlvl.com/networking/port-numbers/119/)
- [Port 123 (NTP)](https://bitlvl.com/networking/port-numbers/123/)
- [Port 135 (MS RPC)](https://bitlvl.com/networking/port-numbers/135/)
- [Port 137 (NetBIOS name)](https://bitlvl.com/networking/port-numbers/137/)
- [Port 138 (NetBIOS datagram)](https://bitlvl.com/networking/port-numbers/138/)
- [Port 139 (NetBIOS session)](https://bitlvl.com/networking/port-numbers/139/)
- [Port 143 (IMAP)](https://bitlvl.com/networking/port-numbers/143/)
- [Port 161 (SNMP)](https://bitlvl.com/networking/port-numbers/161/)
- [Port 162 (SNMP trap)](https://bitlvl.com/networking/port-numbers/162/)
- [Port 179 (BGP)](https://bitlvl.com/networking/port-numbers/179/)
- [Port 194 (IRC)](https://bitlvl.com/networking/port-numbers/194/)
- [Port 389 (LDAP)](https://bitlvl.com/networking/port-numbers/389/)
- [Port 443 (HTTPS)](https://bitlvl.com/networking/port-numbers/443/)
- [Port 445 (SMB)](https://bitlvl.com/networking/port-numbers/445/)
- [Port 464 (Kerberos passwd)](https://bitlvl.com/networking/port-numbers/464/)
- [Port 465 (SMTPS)](https://bitlvl.com/networking/port-numbers/465/)
- [Port 500 (IKE)](https://bitlvl.com/networking/port-numbers/500/)
- [Port 513 (rlogin / who)](https://bitlvl.com/networking/port-numbers/513/)
- [Port 514 (syslog)](https://bitlvl.com/networking/port-numbers/514/)
- [Port 515 (LPD)](https://bitlvl.com/networking/port-numbers/515/)
- [Port 548 (AFP)](https://bitlvl.com/networking/port-numbers/548/)
- [Port 554 (RTSP)](https://bitlvl.com/networking/port-numbers/554/)
- [Port 563 (NNTPS)](https://bitlvl.com/networking/port-numbers/563/)
- [Port 587 (SMTP submission)](https://bitlvl.com/networking/port-numbers/587/)
- [Port 601 (syslog (TCP))](https://bitlvl.com/networking/port-numbers/601/)
- [Port 631 (IPP / CUPS)](https://bitlvl.com/networking/port-numbers/631/)
- [Port 636 (LDAPS)](https://bitlvl.com/networking/port-numbers/636/)
- [Port 749 (Kerberos admin)](https://bitlvl.com/networking/port-numbers/749/)
- [Port 853 (DNS over TLS)](https://bitlvl.com/networking/port-numbers/853/)
- [Port 873 (rsync)](https://bitlvl.com/networking/port-numbers/873/)
- [Port 990 (FTPS (implicit))](https://bitlvl.com/networking/port-numbers/990/)
- [Port 993 (IMAPS)](https://bitlvl.com/networking/port-numbers/993/)
- [Port 995 (POP3S)](https://bitlvl.com/networking/port-numbers/995/)
- [Port 1080 (SOCKS)](https://bitlvl.com/networking/port-numbers/1080/)
- [Port 1194 (OpenVPN)](https://bitlvl.com/networking/port-numbers/1194/)
- [Port 1433 (MS SQL Server)](https://bitlvl.com/networking/port-numbers/1433/)
- [Port 1434 (SQL Server Browser)](https://bitlvl.com/networking/port-numbers/1434/)
- [Port 1521 (Oracle DB)](https://bitlvl.com/networking/port-numbers/1521/)
- [Port 1723 (PPTP)](https://bitlvl.com/networking/port-numbers/1723/)
- [Port 1812 (RADIUS auth)](https://bitlvl.com/networking/port-numbers/1812/)
- [Port 1813 (RADIUS accounting)](https://bitlvl.com/networking/port-numbers/1813/)
- [Port 1883 (MQTT)](https://bitlvl.com/networking/port-numbers/1883/)
- [Port 1900 (SSDP / UPnP)](https://bitlvl.com/networking/port-numbers/1900/)
- [Port 1935 (RTMP)](https://bitlvl.com/networking/port-numbers/1935/)
- [Port 2049 (NFS)](https://bitlvl.com/networking/port-numbers/2049/)
- [Port 2082 (cPanel)](https://bitlvl.com/networking/port-numbers/2082/)
- [Port 2083 (cPanel (TLS))](https://bitlvl.com/networking/port-numbers/2083/)
- [Port 2087 (WHM (TLS))](https://bitlvl.com/networking/port-numbers/2087/)
- [Port 2181 (ZooKeeper)](https://bitlvl.com/networking/port-numbers/2181/)
- [Port 2375 (Docker API)](https://bitlvl.com/networking/port-numbers/2375/)
- [Port 2376 (Docker API (TLS))](https://bitlvl.com/networking/port-numbers/2376/)
- [Port 2379 (etcd client)](https://bitlvl.com/networking/port-numbers/2379/)
- [Port 2380 (etcd peer)](https://bitlvl.com/networking/port-numbers/2380/)
- [Port 2888 (ZooKeeper peers)](https://bitlvl.com/networking/port-numbers/2888/)
- [Port 3000 (dev servers)](https://bitlvl.com/networking/port-numbers/3000/)
- [Port 3128 (Squid proxy)](https://bitlvl.com/networking/port-numbers/3128/)
- [Port 3268 (AD Global Catalog)](https://bitlvl.com/networking/port-numbers/3268/)
- [Port 3306 (MySQL / MariaDB)](https://bitlvl.com/networking/port-numbers/3306/)
- [Port 3389 (RDP)](https://bitlvl.com/networking/port-numbers/3389/)
- [Port 3478 (STUN / TURN)](https://bitlvl.com/networking/port-numbers/3478/)
- [Port 3690 (Subversion)](https://bitlvl.com/networking/port-numbers/3690/)
- [Port 3888 (ZooKeeper election)](https://bitlvl.com/networking/port-numbers/3888/)
- [Port 4000 (dev servers)](https://bitlvl.com/networking/port-numbers/4000/)
- [Port 4011 (PXE proxyDHCP)](https://bitlvl.com/networking/port-numbers/4011/)
- [Port 4200 (Angular dev)](https://bitlvl.com/networking/port-numbers/4200/)
- [Port 4369 (EPMD)](https://bitlvl.com/networking/port-numbers/4369/)
- [Port 4443 (HTTPS alt)](https://bitlvl.com/networking/port-numbers/4443/)
- [Port 4500 (IPsec NAT-T)](https://bitlvl.com/networking/port-numbers/4500/)
- [Port 5000 (dev servers)](https://bitlvl.com/networking/port-numbers/5000/)
- [Port 5001 (DSM (TLS) / iperf3)](https://bitlvl.com/networking/port-numbers/5001/)
- [Port 5060 (SIP)](https://bitlvl.com/networking/port-numbers/5060/)
- [Port 5061 (SIP over TLS)](https://bitlvl.com/networking/port-numbers/5061/)
- [Port 5173 (Vite dev)](https://bitlvl.com/networking/port-numbers/5173/)
- [Port 5222 (XMPP client)](https://bitlvl.com/networking/port-numbers/5222/)
- [Port 5269 (XMPP server-to-server)](https://bitlvl.com/networking/port-numbers/5269/)
- [Port 5353 (mDNS)](https://bitlvl.com/networking/port-numbers/5353/)
- [Port 5432 (PostgreSQL)](https://bitlvl.com/networking/port-numbers/5432/)
- [Port 5555 (ADB)](https://bitlvl.com/networking/port-numbers/5555/)
- [Port 5601 (Kibana)](https://bitlvl.com/networking/port-numbers/5601/)
- [Port 5672 (AMQP)](https://bitlvl.com/networking/port-numbers/5672/)
- [Port 5900 (VNC)](https://bitlvl.com/networking/port-numbers/5900/)
- [Port 5938 (TeamViewer)](https://bitlvl.com/networking/port-numbers/5938/)
- [Port 6033 (ProxySQL)](https://bitlvl.com/networking/port-numbers/6033/)
- [Port 6379 (Redis)](https://bitlvl.com/networking/port-numbers/6379/)
- [Port 6432 (PgBouncer)](https://bitlvl.com/networking/port-numbers/6432/)
- [Port 6443 (Kubernetes API)](https://bitlvl.com/networking/port-numbers/6443/)
- [Port 6514 (syslog over TLS)](https://bitlvl.com/networking/port-numbers/6514/)
- [Port 6667 (IRC)](https://bitlvl.com/networking/port-numbers/6667/)
- [Port 6697 (IRC over TLS)](https://bitlvl.com/networking/port-numbers/6697/)
- [Port 6881 (BitTorrent)](https://bitlvl.com/networking/port-numbers/6881/)
- [Port 7000 (Cassandra)](https://bitlvl.com/networking/port-numbers/7000/)
- [Port 7001 (WebLogic / Cassandra SSL)](https://bitlvl.com/networking/port-numbers/7001/)
- [Port 8000 (dev servers)](https://bitlvl.com/networking/port-numbers/8000/)
- [Port 8008 (HTTP alt)](https://bitlvl.com/networking/port-numbers/8008/)
- [Port 8080 (HTTP alt)](https://bitlvl.com/networking/port-numbers/8080/)
- [Port 8081 (HTTP alt)](https://bitlvl.com/networking/port-numbers/8081/)
- [Port 8086 (InfluxDB)](https://bitlvl.com/networking/port-numbers/8086/)
- [Port 8088 (HTTP alt / Hadoop)](https://bitlvl.com/networking/port-numbers/8088/)
- [Port 8118 (Privoxy)](https://bitlvl.com/networking/port-numbers/8118/)
- [Port 8123 (ClickHouse HTTP)](https://bitlvl.com/networking/port-numbers/8123/)
- [Port 8200 (Vault)](https://bitlvl.com/networking/port-numbers/8200/)
- [Port 8333 (Bitcoin)](https://bitlvl.com/networking/port-numbers/8333/)
- [Port 8443 (HTTPS alt)](https://bitlvl.com/networking/port-numbers/8443/)
- [Port 8448 (Matrix federation)](https://bitlvl.com/networking/port-numbers/8448/)
- [Port 8500 (Consul)](https://bitlvl.com/networking/port-numbers/8500/)
- [Port 8554 (RTSP alt)](https://bitlvl.com/networking/port-numbers/8554/)
- [Port 8883 (MQTT over TLS)](https://bitlvl.com/networking/port-numbers/8883/)
- [Port 9000 (PHP-FPM / SonarQube / Portainer)](https://bitlvl.com/networking/port-numbers/9000/)
- [Port 9001 (Tor ORPort / Supervisor)](https://bitlvl.com/networking/port-numbers/9001/)
- [Port 9042 (Cassandra CQL)](https://bitlvl.com/networking/port-numbers/9042/)
- [Port 9050 (Tor SOCKS)](https://bitlvl.com/networking/port-numbers/9050/)
- [Port 9090 (Prometheus)](https://bitlvl.com/networking/port-numbers/9090/)
- [Port 9092 (Kafka)](https://bitlvl.com/networking/port-numbers/9092/)
- [Port 9093 (Alertmanager)](https://bitlvl.com/networking/port-numbers/9093/)
- [Port 9100 (JetDirect / node_exporter)](https://bitlvl.com/networking/port-numbers/9100/)
- [Port 9117 (Jackett)](https://bitlvl.com/networking/port-numbers/9117/)
- [Port 9200 (Elasticsearch)](https://bitlvl.com/networking/port-numbers/9200/)
- [Port 9300 (Elasticsearch transport)](https://bitlvl.com/networking/port-numbers/9300/)
- [Port 9418 (git)](https://bitlvl.com/networking/port-numbers/9418/)
- [Port 9443 (Portainer / HTTPS alt)](https://bitlvl.com/networking/port-numbers/9443/)
- [Port 9735 (Lightning Network)](https://bitlvl.com/networking/port-numbers/9735/)
- [Port 10000 (Webmin)](https://bitlvl.com/networking/port-numbers/10000/)
- [Port 10250 (kubelet)](https://bitlvl.com/networking/port-numbers/10250/)
- [Port 10443 (HTTPS alt)](https://bitlvl.com/networking/port-numbers/10443/)
- [Port 11211 (Memcached)](https://bitlvl.com/networking/port-numbers/11211/)
- [Port 15672 (RabbitMQ management)](https://bitlvl.com/networking/port-numbers/15672/)
- [Port 16379 (Redis Cluster bus)](https://bitlvl.com/networking/port-numbers/16379/)
- [Port 20000 (RTP range end / Usermin)](https://bitlvl.com/networking/port-numbers/20000/)
- [Port 25565 (Minecraft)](https://bitlvl.com/networking/port-numbers/25565/)
- [Port 25672 (RabbitMQ inter-node)](https://bitlvl.com/networking/port-numbers/25672/)
- [Port 26379 (Redis Sentinel)](https://bitlvl.com/networking/port-numbers/26379/)
- [Port 27015 (Source engine games)](https://bitlvl.com/networking/port-numbers/27015/)
- [Port 27017 (MongoDB)](https://bitlvl.com/networking/port-numbers/27017/)
- [Port 30303 (Ethereum P2P)](https://bitlvl.com/networking/port-numbers/30303/)
- [Port 32400 (Plex)](https://bitlvl.com/networking/port-numbers/32400/)
- [Port 33060 (MySQL X Protocol)](https://bitlvl.com/networking/port-numbers/33060/)
- [Port 33434 (traceroute)](https://bitlvl.com/networking/port-numbers/33434/)
- [Port 49152 (Dynamic / ephemeral range starts)](https://bitlvl.com/networking/port-numbers/49152/)
- [Port 51820 (WireGuard)](https://bitlvl.com/networking/port-numbers/51820/)
- [Port 65535 (Highest port)](https://bitlvl.com/networking/port-numbers/65535/)

## Other

- [About](https://bitlvl.com/about/): what bitlvl is and how it is built
- [Privacy](https://bitlvl.com/privacy/): no accounts, no uploads, no content tracking