Single-purpose developer utilities. Your data never leaves your browser.
Pretty-print, minify, and validate JSON with clear error positions.
Compare two blocks of text with line-level diff and intra-line highlights.
Convert Unix epoch timestamps to human dates and back, live.
Decode a JWT header and payload, with exp/iat/nbf humanized.
UTF-8-safe Base64 encode/decode, with a URL-safe variant.
Test a JavaScript regular expression against sample text.
Plain-English cron description with its next 5 run times.
Percent-encode or decode URLs and query strings, component or full-URL.
Convert identifiers between camel, snake, kebab, Pascal, CONSTANT and more.
Convert numbers between decimal, hex, octal and binary — BigInt-exact.
Convert colors between HEX, RGB, HSL and HWB, with a WCAG contrast checker.
Convert CSV to JSON — RFC 4180 quoting, delimiter auto-detect, type inference.
IPv4 subnet math — network, broadcast, usable range, masks and host counts.
Encode or decode HTML entities — named, numeric and hex forms.
Build a 5-field cron expression from presets or fields, with a live preview.
Sort, dedupe, trim, reverse and re-delimit lists of lines.
Break a URL into protocol, host, path segments and decoded query params.
Unix permission grid with octal, symbolic and special-bit sync.
Compare two JSON documents — added, removed and changed values by path.
Pretty-print or minify XML, with clear parse-error reporting.
Convert a JSON array to CSV — dot-path flattening, RFC 4180 quoting.
Turn CSV or TSV into an aligned GitHub-flavored Markdown table.
Searchable reference of every HTTP status code, official and vendor.
Convert a curl command into JavaScript fetch and Python requests code.
Pretty-print or minify CSS — calc()-safe, strings and url() untouched.
Create and sign a JWT with HS256/384/512 — WebCrypto, fully in-browser.
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