Explore APIs

Send email notification for payment confirmations, alerts, receipts.

Curated Bitcoin coinbase scriptSig messages (printable ASCII only). Pool tags, BIP-comment campaigns, political statements. Window up to 7d.

Summarise IPv4 or IPv6 CIDR blocks into the minimal set (merging adjacent and overlapping blocks) plus the covering supernet.

Parse a Cache-Control value, explain each directive, compute freshness and flag conflicts or leaks.

WCAG contrast ratio between two hex colors with AA and AAA pass/fail for normal and large text.

Compare growth classes (n, n log n, n^2, 2^n, n!) at a given n: operation counts, run time, largest n a time budget allows.

Country for an ITU E.164 calling code or international number prefix, such as +44 or +1 876; flags shared codes.

Bitcoin network health: tip height, block pace vs 10 minutes, difficulty retarget forecast, hashrate trend and Lightning size.

Write a money amount in words for a cheque (EN/ES/FR/DE): you give the currency names, no rates; words or 56/100 cents.

Parse CSV text (quotes, escaped quotes, embedded commas and newlines) into JSON rows, detecting the delimiter.

CAA records for a domain (walking up to parent names): which CAs may issue certificates, wildcard rules and reporting contacts.

Convert a number between bases 2 to 36 exactly (binary, octal, decimal, hex), with big-integer precision.

Live universal sky snapshot, no inputs: geocentric ecliptic longitudes for 13 bodies (Sun through Pluto, Chiron, lunar nodes) with zodiac sign/degree and 64-gate wheel placements, current moon phase and illumination, active retrogrades, and a 30-day almanac of upcoming stations and lunations. JPL-validated ephemeris. JSON. $0.01 USDC via x402, or API key.

Metres per pixel, map scale (1:N) and tile width on the ground for a zoom level and latitude.

Convert an airport code between IATA (3 letters) and ICAO (4 letters) and validate the format; reports unknown codes.

Percent-encode or decode text as URL component, path, query or form data (UTF-8), with byte counts.

Convert text to camelCase, PascalCase, snake_case, kebab-case, CONSTANT_CASE, Title Case, sentence case and a URL slug.

Buy a site upload slot. Upload a zip file, then activate to extract and serve as a static site.

Exact age in years, months and days from a birth date as of a date, plus next birthday and days until it.

Compute or verify the GS1 mod-10 check digit for EAN-8, UPC-A, EAN-13, ITF-14 (GTIN-14) and SSCC numbers.

Time one GET to a URL: DNS, connect, TLS, first byte and total ms, plus status, content type and size read.

Convert power between dBm, dBW, mW and W, and the RMS and peak voltage across 50 ohms (or your impedance).