yutils

Encode text to Base64 or decode Base64 back to text. Runs entirely in your browser, no data sent to any server.

Percent-encode text for safe use in URLs, or decode percent-encoded URLs back to text. Runs entirely in your browser.

Generate UUID v4 (random), UUID v7 (time-ordered, RFC 9562), or ULID identifiers — all client-side via crypto.

Decode the header and payload of a JSON Web Token. Signature is not verified (a public key is required). The token is processed entirely in your browser.

Generate a signed JSON Web Token with HS256/HS384/HS512 (HMAC-SHA). Payload and secret stay in your browser — Web Crypto API based.

Compute SHA-1, SHA-256, SHA-384, or SHA-512 hash of text. Uses the browser's Web Crypto API; no data is sent to any server.

Encode text to hexadecimal or decode hex back to text. Supports UTF-8 multi-byte characters and tolerates whitespace.

Encode HTML special characters (&, <, >, ", ') to entities, or decode named/numeric entities back to text.

Generate cryptographically strong passwords, tokens, random strings, and passphrases with entropy display.

Convert numbers between bases (binary/octal/decimal/hex/base36) using BigInt for large integers. Auto-detects 0b/0o/0x prefixes.

Decompose a URL into protocol, host, path, query parameters, and hash — read-only inspection.

Compute HMAC (Hash-based Message Authentication Code) with SHA-1/256/384/512 using the Web Crypto API.

Verify whether a given HMAC signature matches the message + secret. Constant-time comparison via Web Crypto API.

Compute MD5 hash for text. Note: MD5 is broken for security — checksums and legacy compatibility only.

Convert international domain names to/from Punycode (xn-- encoded ASCII). Uses native URL parser.

Browse and search HTTP status codes (1xx-5xx) with descriptions and common usage.

Parse User-Agent strings into browser, OS, device, and engine fields.

Hash passwords with Bcrypt or verify a plaintext against an existing hash. Configurable salt rounds.

Parse Cookie or Set-Cookie strings into a table. Decode percent-encoded values. Supports Set-Cookie attributes (Path/Domain/Max-Age/SameSite/HttpOnly/Secure).

Compute network address, broadcast, host range, mask, and host count from an IPv4 + CIDR.

Build cURL commands from URL/method/headers/body. Auto-detects JSON content-type.