Transcribe text to Unicode braille (grade-1 / uncontracted English braille), with capital and number signs. Characters with no grade-1 representation are clean 400s.

Sanitize untrusted HTML to a safe allowlist. Keeps common formatting and links but removes dangerous scripting tags, inline event handlers and unsafe URL schemes. Ideal for rendering user-supplied HTML.

Validate a UUID and report its version and variant.

Parse a document (json, json5, jsonc, yaml, xml, csv, tsv, toml, ndjson, ini, env, properties, plist or querystring) and validate it against a JSON Schema. Returns whether it is valid and a list of precise, path-tagged errors. Malformed input or an invalid schema is rejected before payment.

Rebuild a nested object from a single-level object whose keys are delimited paths (default delimiter `.`) — the inverse of flatten. Requires a flat object.

Build braille cells from raised-dot numbers (each cell an array of 1–8). Out-of-range or repeated dots are clean 400s.

Infer a JSON Schema (draft-07) from a sample document in any supported format. Types are inferred, present keys are marked required, and heterogeneous array item schemas are merged. The result validates out of the box with /v1/validate.

Flatten a nested object/array into a single-level object whose keys are the delimited paths to each leaf (default delimiter `.`). Requires an object or array.

Encode a word with the classic Soundex algorithm (letter + 3 digits) for phonetic matching of names.

Encode a word with Double Metaphone, returning a primary and a secondary code to capture alternate pronunciations (useful for non-English names).

Fuzzy-search emoji by name, shortcode or keyword tag, ranked exact → prefix → substring.

Fletcher checksum over the input payload, in 16-bit (default) or 32-bit width. Returns the checksum as an unsigned integer and hex. Non-cryptographic.

Adler-32 checksum (as used by zlib) over the input payload. Faster than CRC-32 but weaker for short inputs. Returns the checksum as an unsigned integer and 8-digit hex. Non-cryptographic.

Generate a random string of a given length from a named charset (alphanumeric, alpha, lower, upper, numeric, hex, base58) or a custom alphabet. Unbiased character selection.

Return the synonyms of an English word, aggregated across all its senses. Optionally filter by part of speech. An unknown word returns found:false with a 200.

Ordinary-least-squares linear regression of y on x: slope, intercept, correlation r and coefficient of determination r². Pass predictAt to also evaluate the fitted line at a given x. Rejected as a clean 400 if lengths differ or x has zero variance.

Convert a decimal string to an exact reduced fraction. For a repeating decimal, set repeat to the number of trailing fractional digits that repeat (e.g. value='0.1666', repeat=1 → 1/6; value='0.3', repeat=1 → 1/3). A non-numeric value is a clean 400.

Shift a non-negative integer left or right by `amount` bits. A right shift is logical (fills with zeros). A left shift grows freely unless a `width` is given, in which case the result is masked to that width and the input must fit it. Returns decimal, hex and binary.

Circularly rotate a non-negative integer left or right within an explicit bit width (bits shifted off one end reappear at the other). The value must fit in `width` bits. Returns decimal, hex and binary.

Inspect a non-negative integer's bit structure: bit length, set-bit count (population count), trailing-zero count, power-of-two test, and hex/binary representations. An optional width zero-pads the binary form.