Developer Utilities
Small developer utilities that save a trip to a random website. Encode and decode Base64, explain a regex, build UTM links, generate QR codes and vCards, and more — the everyday helpers. Free in your browser, and available by API when you need them in a script.
Developer Utilities
Luhn mod-10 check digit
compute and validate any number string free
POST /enc/luhn$0.002Developer Utilities
Luhn mod N check character
any alphabet, free in browser
POST /enc/luhn-mod-n$0.002Developer Utilities
Mailto link builder
encode subject, body, cc and bcc free
POST /enc/mailto-encode$0.002Developer Utilities
Markdown escaper
escape & unescape specials for literal text
POST /enc/markdown-escape$0.002Developer Utilities
Match Rating Approach codex
phonetic name code free online
POST /enc/match-rating$0.002Developer Utilities
Unicode bold text
mathematical bold letters and digits for social media
POST /enc/mathematical-bold$0.002Developer Utilities
Australia Medicare check digit
compute or validate card numbers
POST /enc/medicare-australia$0.002Developer Utilities
MEID check digit calculator
compute and validate free
POST /enc/meid$0.002Developer Utilities
MIME B encoded-word
wrap and unwrap Base64 charset headers, free
POST /enc/mime-b-encoding$0.002Developer Utilities
ISO 7064 mod-11 check digit
compute and validate (X for 10)
POST /enc/mod11$0.002Developer Utilities
ISO 7064 mod 97-10 check digits
compute and validate free
POST /enc/mod97$0.002Developer Utilities
Unicode monospace text
plain letters & digits ↔ 𝙷𝚎𝚕𝚕𝚘 style, free
POST /enc/monospace-unicode$0.002Developer Utilities
Morbit cipher
encrypt & decrypt Morse digram digits, free
POST /enc/morbit$0.002Developer Utilities
MurmurHash3 hash calculator
32-bit hex with optional seed
POST /enc/murmur3$0.002Developer Utilities
Japan My Number check digit
compute or validate 12 digits
POST /enc/mynumber-japan$0.002Developer Utilities
Myszkowski transposition cipher
encrypt decrypt with repeated key letters
POST /enc/myszkowski$0.002Developer Utilities
Portuguese NIB check digits
ISO 7064 mod 97-10 free
POST /enc/nib-portugal$0.002Developer Utilities
Spain NIE control letter
compute or validate the check letter
POST /enc/nie-spain$0.002Developer Utilities
Polish NIP check digit
compute and validate free online
POST /enc/nip-poland$0.002Developer Utilities
NPI check digit
compute Luhn with 80840 prefix or validate a 10-digit NPI
POST /enc/npi$0.002Developer Utilities
Chaldean numerology calculator
reduce a name to its number
POST /enc/numerology-chaldean$0.002Developer Utilities
Pythagorean numerology calculator
reduce a name to 1–9
POST /enc/numerology-pythagorean$0.002Developer Utilities
Numeronym generator
make i18n-style abbreviations, free
POST /enc/numeronym$0.002Developer Utilities
NYSIIS encoder
New York State phonetic name code, free
POST /enc/nysiis$0.002Developer Utilities
Ook! encoder and decoder
text ↔ Ook esolang, free
POST /enc/ook-encode$0.002Developer Utilities
Opish language translator
insert op after consonants, free
POST /enc/opish$0.002Developer Utilities
Indian PAN card validator
format and entity type free
POST /enc/pan-india$0.002Developer Utilities
Parity bit calculator
even and odd parity for bytes and bit strings
POST /enc/parity-bit$0.002Developer Utilities
Sweden personnummer check digit
Luhn over date and serial, or validate
POST /enc/personnummer-sweden$0.002Developer Utilities
Phone keypad multi-tap encoder
convert text to 2=ABC key presses
POST /enc/phone-multitap$0.002Developer Utilities
Pigpen cipher
encode & decode Masonic grid symbols free online
POST /enc/pigpen$0.002Developer Utilities
Police phonetic alphabet
Adam Boy Charlie David, free
POST /enc/police-phonetic$0.002Developer Utilities
Pollux cipher encoder and decoder
Morse digits key, free
POST /enc/pollux$0.002Developer Utilities
Porta cipher
encrypt or decrypt with a passphrase, free
POST /enc/porta$0.002Developer Utilities
Printf format escaper
double percent signs & backslash escapes
POST /enc/printf-escape$0.002Developer Utilities
Q-code translator
expand and compress ham radio Q-codes free
POST /enc/q-code$0.002Developer Utilities
Query string parser
parse and encode URL parameters free
POST /enc/query-string$0.002Developer Utilities
Q-encoding header encoder
RFC 2047 encode/decode for email headers
POST /enc/quoted-printable-q$0.002Developer Utilities
Refined Soundex encoder
full-length phonetic name code, free
POST /enc/refined-soundex$0.002Developer Utilities
Regex metacharacter escaper
literal string ↔ safe pattern
POST /enc/regex-escape$0.002Developer Utilities
Poland REGON check digit
compute or validate 9- and 14-digit numbers
POST /enc/regon-poland$0.002Developer Utilities
RFC 1751 S/KEY word encoder
hex keys to English words
POST /enc/rfc1751$0.002Developer Utilities
Czech rodné číslo check
date and mod-11 validate free
POST /enc/rodne-cislo$0.002Developer Utilities
ROT8000 Unicode cipher
encode & decode BMP text, free
POST /enc/rot8000$0.002Developer Utilities
ROT-N cipher
rotate letters by any shift N, free online
POST /enc/rot-n$0.002Developer Utilities
RTF Unicode escaper
text ↔ \uN decimal control words
POST /enc/rtf-unicode$0.002Developer Utilities
Ecuador RUC check digit
validate modulo 10/11 free
POST /enc/ruc-ecuador$0.002Developer Utilities
Running-key cipher
encrypt & decrypt with a long text key stream
POST /enc/running-key$0.002Developer Utilities
Unicode sans-serif text
mathematical sans-serif letters & digits, free
POST /enc/sans-serif-unicode$0.002Developer Utilities
Unicode cursive script text
fancy mathematical script letters, free
POST /enc/script-unicode$0.002Developer Utilities
SEDOL check digit
compute and validate security codes free
POST /enc/sedol$0.002Developer Utilities
Shell argument quoter
POSIX quote & unquote for safe argv
POST /enc/shell-escape$0.002Developer Utilities
Monoalphabetic substitution cipher
encrypt & decrypt with a 26-letter key
POST /enc/simple-substitution$0.002Developer Utilities
Canadian SIN check digit
Luhn for 8 digits or validate a 9-digit SIN
POST /enc/sin-canada$0.002Developer Utilities
French SIREN Luhn check
compute and validate nine-digit IDs free
POST /enc/siren-france$0.002Developer Utilities
French SIRET Luhn check
validate 14-digit establishment number
POST /enc/siret-france$0.002Developer Utilities
Soundex encoder
American Soundex code for names, free
POST /enc/soundex$0.002Developer Utilities
Spanish spelling alphabet
Antonio Burgos Carmen, free encode & decode
POST /enc/spanish-spelling$0.002Developer Utilities
SSCC-18 check digit calculator
compute and validate free
POST /enc/sscc$0.002Developer Utilities
Germany tax ID check digit
Steuer-ID (Identifikationsnummer) calculator
POST /enc/steuer-id-germany$0.002