Media
Decode HEIC photos to verified 24/32-bit or high-precision 48/64-bit PNG files.
heic-to-pngData Visualization
Bin numeric data into intervals and draw a histogram to visualize a statistical distribution
histogram-makerCryptography
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-verifierDevelopment
Upload any binary file and inspect it as a classic hex dump with offset, hex bytes, and ASCII columns (read-only)
hex-editorFormat Conversion
Convert text to and from hexadecimal strings with flexible spacing, prefix (0x/\x/U+), and case options
hex-to-stringValidation
Audit heading structure from a live URL or pasted HTML, then flag skipped levels, multiple h1 usage, style-only heading abuse, and title metadata drift
heading-hierarchy-auditorMath & Numbers
Convert horsepower to kilowatts with configurable decimal precision
hp-to-kwMath & Numbers
Convert horsepower to watts with configurable decimal precision
hp-to-wattMath & Numbers
Convert hours to days with configurable decimal precision
hours-to-daysMath & Numbers
Convert hectares to square meters with configurable decimal precision
hectare-to-square-meterMath & Numbers
Convert hectares to acres with configurable decimal precision
hectare-to-acre