Every section has an address, every claim has a source

2026-09-06T00:00:00Z

Every field type has its own anchor. /api/types.json publishes a documentation link per type, and 67 of the 68 pointed at a fragment that did not exist — they all landed at the top of the reference. They resolve now, and each type carries a real definition in the page's structured data instead of just a name. Section anchors and a contents list. 337 headings had no id, so a page could only be linked as a whole. Every content section is addressable now, and the longer pages open with an "On this page" list. The standards are linked. Pages that mention RFC 4180, RFC 2606 and 6761, RFC 4122, ISO 8601, E.164 or JSON Schema draft 2020-12 now link the document that defines them, rather than asking you to take the claim on trust. Questions answered where they are asked. Use cases, database, mock API, QA, spreadsheet, guide and methodology pages gained an FAQ; the five "alternative to" pages gained a side-by-side table. Two counts were wrong. The site advertised a vague “60+” in 24 places and the exact number in a handful of others; there are 68 field types. It also claimed nine name locales where there are eight locales — the ninth entry in the dropdown is “any”, which is not one. Both counts are asserted by the test suite now, against the generator itself. Every page shows when it was last updated, and there is a full-text copy of the site in one file alongside llms.txt.

Format converters, and files you can actually download

2026-09-05T00:00:00Z

Five format converters. CSV to JSON, JSON to CSV, CSV to SQL, JSON to SQL and XML to JSON. They run in your browser like everything else here, so nothing is uploaded. Each page documents the decisions the conversion forces — what happens to a leading zero, to a nested object, to a repeated XML element. Static sample files. The sample pages now offer real files under /samples/: users, employees, orders and sensor readings, as CSV, JSON and SQL, at 100 and 1,000 rows. They are generated from a fixed seed and committed, so a link to one keeps returning the same bytes. Public domain, no attribution needed. A generator on every generator page. UUIDs, names, emails and the rest now generate a live example on the page instead of describing one. The button beside it opens the full builder on that page's schema — it used to open the default Users template, which was unhelpful on a page about IBANs. A machine-readable field catalogue at /api/types.json, generated from the generator itself.

Fun Data Playground — changelog

Every section has an address, every claim has a source

Format converters, and files you can actually download