Tokens, hashes, cron lines, headers.
category
Dev
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JWT Decoder
Decode a JWT's header and payload, and check its exp/nbf claims — entirely in your browser, never sent anywhere.
↗Hash & Encoding
46 hash algorithms and URL encode/decode — computed locally as you type, no network.
↗File Hash Calculator
MD5, SHA-1/256/384/512, SHA3, BLAKE2b, BLAKE3, RIPEMD-160, Whirlpool, SM3, CRC32 — streamed through WebAssembly, entirely on-device.
↗User-Agent Parser
Decode any User-Agent string into browser, engine, OS and device type — pre-filled with your own, works on any UA pasted from a server log.
↗Security Headers Analyzer
Paste HTTP response headers to grade a site's security posture — CSP directive-by-directive, HSTS, frame protection — entirely offline.
↗Cron Parser
Decode a cron expression — field-by-field validation, plain-English description and the next run times in your timezone, entirely offline.
↗Unix Timestamp Converter
Epoch to ISO 8601 and back — unit auto-detection from magnitude, any IANA time zone, relative time and a live second/millisecond clock, entirely offline.
↗Base64 Encode / Decode
UTF-8 Base64 encode/decode in standard or URL-safe alphabet with optional padding, byte counts and alphabet auto-detection on decode — offline; the URL holds only the options.
↗chmod Calculator
Convert Unix permissions between octal (755), symbolic (rwxr-xr-x) and checkboxes, apply chmod expressions, derive umask results and copy the ready command — offline.