Validation
Validate license plate formats from multiple countries including China, USA, Japan, and more
license-plate-validatorSecurity
Decode JWT tokens
jwt-decoderSecurity
Generate public/private key pairs for various cryptographic algorithms
key-pair-generatorSecurity
Generate JWT tokens with custom claims and algorithms
jwt-generatorValidation
Validate International Securities Identification Numbers (ISO 6166 ISIN) with Luhn check-digit verification, country/issuer prefix and NSIN breakdown.
isin-validatorValidation
Validate ISBN-10 and ISBN-13 book number formats with checksum verification
isbn-validatorValidation
Validate IPv4 and IPv6 addresses with CIDR notation support
ip-address-validatorValidation
Validate IMEI numbers for mobile devices using Luhn checksum algorithm
imei-validatorValidation
Validate IMSI numbers for mobile subscribers with MCC/MNC analysis
imsi-validatorCryptography
Compute and audit MACs across HMAC-SHA-2/SHA-3, keyed BLAKE2, BLAKE3, KMAC and Poly1305 with official known-answer self-tests, key/tag-length linting and a cross-construction compatibility matrix.
hmac-blake3-sha3-keccak-keyed-hash-and-mac-construction-linterCryptography
Hash the same input with MD5, SHA-1, SHA-256, SHA-512, BLAKE2b, and BLAKE3 at the same time and compare them side by side: output length, hex/Base64 digest, security status (broken / modern), and a relative speed benchmark. Great for teaching, choosing a hashing algorithm, or sanity-checking checksums.
hash-algorithm-comparatorSecurity
Compute an HMAC message-authentication signature over a message + shared secret using SHA-1/SHA-2/SHA-3/BLAKE2, or verify an incoming signature against the secret — with webhook presets for Stripe / Slack / GitHub and constant-time comparison
hmac-generator-verifier