the402 x402 endpoint directory

Parse a URL query string into an object, or build one from an object. mode: parse (default) | build.

Remove duplicate lines, preserving first-seen order. Returns the deduped text and how many were removed.

Encode text to HTML entities or decode them back. mode: encode (default) or decode.

Base32 (RFC 4648) encode or decode text. mode: encode (default) or decode.

Look up a MIME type by file extension (?ext=png) or extensions by MIME type (?type=image/png). Covers ~50 common types

Parse a URL into components: protocol, host, port, path, query params (decoded), hash, origin, punycode hostname.

Convert text between camelCase, PascalCase, snake_case, kebab-case, CONSTANT_CASE, Title Case, lower, UPPER.

Decode a JWT without verification: header, payload, expiry status, and time remaining. (Decoding only — signatures are

HMAC signature of a message with a shared key. Algorithms: sha256 (default), sha512, sha1. Returns hex and base64.

List the wallets you've granted access to your namespace, with their mode and expiry.

Get the day number within the year (1-366) for any date, plus days remaining, leap-year status, percent of year comple

Get the ISO 8601 week number, ISO day-of-week, quarter, and day-of-year for any date. Useful for fiscal/reporting cale

Convert text between naming conventions: camelCase, PascalCase, snake_case, kebab-case, CONSTANT_CASE, and Title Case.

HKDF extract-then-expand (RFC 5869) — derive output keying material from initial keying material, an optional salt, an

Standard matrix multiplication of two 2D arrays: A[m×k] × B[k×n] → C[m×n]. Validates that inner dimensions match. Each

Convert an internationalized domain name to Punycode (ASCII-compatible encoding, RFC 3492) or decode Punycode back to

Check XML well-formedness: balanced open/close tags, proper nesting, unescaped entities. No DTD/schema validation — sy

Compute Jaccard similarity, overlap coefficient, and Sorensen-Dice coefficient between two texts at the word level. Re

Parse a datetime from any format (ISO 8601, Unix timestamp in seconds or milliseconds, RFC 2822, or natural date strin

Top DEX pools (Uniswap, Sushi, Curve, Aerodrome, etc.) ranked by current TVL — filterable by chain and project. Source

Two-way CSS named color tool. Pass a name (e.g. "rebeccapurple") to get its canonical RGB/hex; pass a hex/rgb color to

Convert a nominal annual rate (APR) compounded m times per year into the effective annual rate (EAR / APY): (1 + apr/m

Compound annual growth rate between a beginning and ending value over N years: (end/begin)^(1/years) - 1. Also returns

Build the full per-period amortization schedule for a fully-amortizing loan. Each row reports the period number, payme

Holt's linear trend method — level + trend (no seasonality). Two smoothing parameters: alpha (level) and beta (trend).

Compute simple (SMA) and exponential (EMA) moving averages over a numeric series. Returns one value per input position

Run the same input through gzip, brotli, and raw deflate at max settings and report each one's output size and ratio.

Compress a string with gzip (RFC 1952) and return it as base64. Reports input bytes, output bytes, and the compression

Extract a <table> from an HTML string as JSON rows (header-keyed) or CSV. Useful for prices, schedules, sports stats,

Convert a JSON value to indented XML — the reverse of xml-to-json. Objects become nested elements, arrays repeat their

Pure-CPU helper: turn a B20 feature string (e.g. base.b20_asset) into its bytes32 feature id and ready-to-send isActiv

Search autocomplete: query suggestions for a partial input as a flat JSON array. Useful for query expansion, did-you-m

Validate an ISBN-10 or ISBN-13 checksum (hyphens/spaces ignored) and report which format it is.

Count business days (Mon–Fri) between two dates, inclusive of the start, exclusive of the end. Optional list of holida

Descriptive statistics for an array of numbers: count, sum, mean, median, mode, min, max, range, variance, stddev, and

Deep-merge two JSON objects (b wins on conflicts; arrays are concatenated).

Sort the lines of a text. order: asc (default) | desc | numeric. unique:true removes duplicates; ci:true is case-insen

Encode text to Morse code or decode it back. mode: encode (default) or decode. Words separated by ' / '.

Base58 encode or decode text (Bitcoin/IPFS alphabet). mode: encode (default) or decode.

Parse a semantic version, or compare two (a vs b → -1/0/1, with greater/lesser flags).

Difference between two dates/times in ms, seconds, minutes, hours, days, and a human summary.

Turn any text into a URL-safe slug (lowercase, hyphenated, diacritics stripped).

Generate cryptographically random passwords. ?length=8..128 (default 24), ?symbols=true|false (default true), ?count=1

Percent-encode or decode a string for URLs. mode: encode (default) or decode. component: true (default) uses encodeURI

Revoke a previously granted wallet's access to your namespace.

DNS lookup for a domain. Supported record types: A, AAAA, MX, TXT, NS, CNAME.

Convert a value between units of measure: mass (g, kg, mg, lb, oz, t, st), length (m, km, cm, mm, in, ft, yd, mi), vol

agenticweb.nl ping — liveness + payment loop smoke test. Payment constitutes acceptance of the terms at agenticweb.nl/

Genuinely fascinating fun fact about science, history, nature, or the universe.

Decode QR/barcodes from a base64-encoded image; returns each detected code's type, decoded text, bounding rect, and po