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
Argentine CUIT/CUIL check digit
compute and validate free
POST /enc/cuit-argentina$0.002Developer Utilities
Mexico CURP check digit
compute and validate free
POST /enc/curp-mexico$0.002Developer Utilities
CUSIP check digit calculator
compute and validate free
POST /enc/cusip$0.002Developer Utilities
Dancing Men cipher
encode & decode Doyle stick figures, free
POST /enc/dancing-men$0.002Developer Utilities
Digrafid cipher
encrypt & decrypt digraphs with two keyed alphabets, free
POST /enc/digrafid$0.002Developer Utilities
djb2 hash calculator
32-bit Bernstein string hash in hex
POST /enc/djb2$0.002Developer Utilities
DNA base encoder
text ↔ A/C/G/T, free online
POST /enc/dna-encode$0.002Developer Utilities
Spanish DNI/NIF letter calculator
modulo-23 control letter free
POST /enc/dni-spain$0.002Developer Utilities
Double Metaphone encoder
primary & alternate phonetic keys, free
POST /enc/double-metaphone$0.002Developer Utilities
Dutch spelling alphabet
spell or decode Anna Bernard Cornelis, free
POST /enc/dutch-spelling$0.002Developer Utilities
Dvorak QWERTY converter
fix wrong keyboard layout typing, free
POST /enc/dvorak-qwerty$0.002Developer Utilities
EAN-13 check digit calculator
compute and validate free
POST /enc/ean-check$0.002Developer Utilities
EBCDIC encoder
ASCII ↔ IBM code page 037, free
POST /enc/ebcdic$0.002Developer Utilities
Ecoji emoji encoder
encode and decode base-1024 emoji text
POST /enc/ecoji$0.002Developer Utilities
Bulgarian EGN check digit
compute and validate free online
POST /enc/egn-bulgaria$0.002Developer Utilities
US EIN format validator
check prefix and IRS campus free
POST /enc/ein-us$0.002Developer Utilities
HTML named to numeric entities
© ↔ ©, free
POST /enc/entity-named-to-numeric$0.002Developer Utilities
Fibonacci coding (Zeckendorf)
encode and decode positive integers
POST /enc/fibonacci-coding$0.002Developer Utilities
Fletcher-32 checksum
16-bit word hex calculator, free
POST /enc/fletcher32$0.002Developer Utilities
Norwegian fødselsnummer check digits
compute and validate free
POST /enc/fnr-norway$0.002Developer Utilities
FNV-1 hash calculator
32/64-bit hex non-cryptographic hash
POST /enc/fnv1$0.002Developer Utilities
FNV-1a hash
32 and 64 bit non-cryptographic calculator, free
POST /enc/fnv1a$0.002Developer Utilities
Fractionated Morse
encrypt or decrypt with a keyword alphabet, free
POST /enc/fractionated-morse$0.002Developer Utilities
Unicode Fraktur text
convert letters to blackletter Fraktur and back
POST /enc/fraktur-unicode$0.002Developer Utilities
French spelling alphabet
Anatole Berthe Célestin encode & decode, free
POST /enc/french-spelling$0.002Developer Utilities
English gematria calculator
A=6, B=12 word value free
POST /enc/gematria-english$0.002Developer Utilities
Hebrew gematria calculator
letter values and total free
POST /enc/gematria-hebrew$0.002Developer Utilities
Ordinal gematria calculator
A=1 to Z=26 word value free
POST /enc/gematria-ordinal$0.002Developer Utilities
Gibberish language translator
idig encode and decode free
POST /enc/gibberish-gik$0.002Developer Utilities
Grandpré cipher
encrypt & decrypt with keyword-row coordinates, free
POST /enc/grandpre$0.002Developer Utilities
Turning grille cipher
encrypt & decrypt with a rotating mask
POST /enc/grille-cipher$0.002Developer Utilities
India GSTIN check digit
compute or validate base-36 checksum
POST /enc/gstin-india$0.002Developer Utilities
GTIN-14 check digit
compute from 13 digits or validate a 14-digit code
POST /enc/gtin14$0.002Developer Utilities
Hex dump viewer
offsets, hex columns and ASCII gutter, free
POST /enc/hexdump$0.002Developer Utilities
Hill cipher 2×2
encrypt & decrypt with a key matrix mod 26
POST /enc/hill-2x2$0.002Developer Utilities
Hill cipher 3×3
encrypt or decrypt with a nine-number key matrix, free
POST /enc/hill-3x3$0.002Developer Utilities
Hong Kong ID check digit
compute and validate free
POST /enc/hkid$0.002Developer Utilities
Homoglyph text converter
Latin ↔ confusable Unicode
POST /enc/homoglyph$0.002Developer Utilities
Decimal HTML entities converter
&#N; encode and decode, free
POST /enc/html-entities-decimal$0.002Developer Utilities
Named HTML entities encoder and decoder
amp, lt, copy, nbsp
POST /enc/html-entities-named$0.002Developer Utilities
IBAN check digit generator
mod 97-10 from country, bank and account
POST /enc/iban-generate$0.002Developer Utilities
IDNA domain encoder
Unicode hostnames to xn-- and back, free
POST /enc/idna$0.002Developer Utilities
IMEI check digit
compute Luhn for 14 digits or validate a 15-digit IMEI
POST /enc/imei$0.002Developer Utilities
Intel HEX encoder
encode, decode and verify firmware records free
POST /enc/intel-hex$0.002Developer Utilities
Internet checksum (RFC 1071)
IP/TCP/UDP 16-bit calculator, free
POST /enc/internet-checksum$0.002Developer Utilities
ISBN-10 check digit
compute and validate free, X for ten
POST /enc/isbn10$0.002Developer Utilities
ISBN-13 check digit
compute from 12 digits or validate a 13-digit barcode
POST /enc/isbn13$0.002Developer Utilities
ISBN-10 to ISBN-13 converter
check digit both ways free
POST /enc/isbn-convert$0.002Developer Utilities
ISIN check digit
compute Luhn for 11-char body or validate a 12-char ISIN
POST /enc/isin$0.002Developer Utilities
ISMN check digit
compute and validate thirteen-digit music numbers free
POST /enc/ismn$0.002Developer Utilities
ISO 7064 check digit
MOD 11-2 and MOD 37-2 free
POST /enc/iso7064$0.002Developer Utilities
Wabun Morse code translator
Japanese kana encode & decode free
POST /enc/japanese-wabun$0.002Developer Utilities
JMBG check digit
compute or validate the Yugoslav number
POST /enc/jmbg$0.002Developer Utilities
JavaScript string escaper
escape & unescape quotes, newlines, unicode
POST /enc/js-string-escape$0.002Developer Utilities
JSON string escaper
escape & unescape quotes, backslashes, controls
POST /enc/json-string-escape$0.002Developer Utilities
Iceland kennitala check digit
compute or validate the mod-11 digit
POST /enc/kennitala-iceland$0.002Developer Utilities
Keyboard coordinate cipher
QWERTY row/column encode & decode, free
POST /enc/keyboard-coords$0.002Developer Utilities
LaTeX escaper
escape & unescape \, &, %, $, _ and other specials
POST /enc/latex-escape$0.002Developer Utilities
LDAP DN escaper
escape & unescape RFC 4514 components
POST /enc/ldap-dn-escape$0.002Developer Utilities
Longitudinal redundancy check (LRC)
XOR check byte in hex
POST /enc/lrc$0.002