Turn an iCal/ICS calendar URL (Google Calendar, Outlook, holidays, events...) into JSON: upcoming events with title, start and end, all-day flag, location, description and link over the next N days; text filter.

Food product facts by barcode (EAN/UPC) from Open Food Facts: name, brand, quantity, Nutri-Score, NOVA processing group, Eco-Score, nutrients per 100 g, allergens, additives, ingredients and countries.

Metadata of a publication by DOI (Crossref): title, authors, journal or publisher, year, type, citation count, references, license, link and an APA-formatted citation.

Book data by ISBN (10 or 13) or search by title and author on Open Library: title, authors, publisher, year, pages, languages, subjects, cover and links.

Query a JSON document with JSONPath, including filters and functions ($.items[?(@.price > 10)].name, $..id...): matching values and their paths. Send the JSON in «datos» or a URL to fetch it.

Check an IP against public threat lists: botnet command-and-control servers (abuse.ch Feodo Tracker), Tor exit nodes and hijacked or spam networks (Spamhaus DROP). For filtering traffic, sign-ups and payments.

What's being read on Hacker News now: top, new, best, Ask HN, Show HN or jobs stories with points, comments, author, age and link. A pulse of tech, AI and startups.

Test a regular expression against a text: every match with position, groups and named groups, plus the result of a substitution if you pass a replacement. Flags i, m, s, x. Time-limited, safe against catastrophic backtracking.

Ethereum blob usage (EIP-4844, the data rollups post): current blob base fee in gwei and USD cost of one blob, blobs per block over the last N blocks and how often blocks were full.

Book data by ISBN (10 or 13) or search by title and author on Open Library: title, authors, publisher, year, pages, languages, subjects, cover and links.

Average US mortgage rates from Freddie Mac's weekly PMMS survey: 30- and 15-year fixed, latest value, weekly and yearly change and recent series.

Average price with taxes of petrol 95, diesel, heating oil and LPG in each EU country (European Commission Weekly Oil Bulletin), in EUR per litre, sorted cheapest first.

Species information by scientific or common name (GBIF): accepted name, full taxonomy (kingdom to species), rank, status, common names, number of occurrence records and countries with most records.

Turn an iCal/ICS calendar URL (Google Calendar, Outlook, holidays, events...) into JSON: upcoming events with title, start and end, all-day flag, location, description and link over the next N days; text filter.

Space weather now from NOAA SWPC: geomagnetic Kp index (recent hours and max), storm level (G0-G5), latest solar X-ray flares, solar wind speed and active alerts. Affects satellites, GPS and power grids.

Postal code lookup in more than 60 countries (ES, US, DE, FR, GB, IT, MX, BR...): places, province or state and coordinates.

Hedera network status: the official HBAR/USD exchange rate the network uses to compute fees (current and next), circulating and total supply, latest block and market price.

Check an IP against public threat lists: botnet command-and-control servers (abuse.ch Feodo Tracker), Tor exit nodes and hijacked or spam networks (Spamhaus DROP). For filtering traffic, sign-ups and payments.

Decode a JWT and verify its signature with the public keys of a JWKS URL (RS256, ES256, EdDSA...) or an HMAC secret, checking expiry, audience and issuer; returns header, claims and the exact reason if invalid. Tokens are not stored.

Validate a Spanish Social Security affiliation number (12 digits: province, number, control) and return the province of registration. Computed locally; nothing stored.