quicktype
Generates typed models and serialisers in many languages from JSON or JSON Schema samples.
why this verdict
Cancel it — switch to ChatGPT
ChatGPT and json-schema-to-typescript now cover the same core job, so there is little reason to run a second tool for it.
- A named launch, not a vibe named, unlinked
- GPT-4 producing typed models and parsers from a pasted JSON payload. OpenAI, March 14, 2023 — no announcement link recorded yet.
- How much of the job it covers all of it editorial call
- The whole core job — the thing the subscription was actually for.
- Is there a free way to do it? yes
- 3 of 3 listed replacements have a usable free tier: ChatGPT, json-schema-to-typescript and Zod.
- What the call is worth nothing to cancel
- No paid entry tier tracked, so there is no subscription to cancel.
- Threatened by
- OpenAI
- Since
- March 14, 2023
- List price
- free
- Per year
- —
The backstory
quicktype took a JSON sample and emitted matching types and parsing code in TypeScript, Swift, Go, Rust and more. It solved a genuinely tedious chore that came up whenever you consumed an unfamiliar API. Language models do the same conversion in a prompt, handle optional and union cases with a nudge, and put the result straight into the file you are editing. The project remains open source and useful, but the workflow it owned now lives inside the editor.
Escape hatches
Converts sample payloads into typed models in any language
openai.com open_in_newDeterministic type generation from JSON Schema in build steps
npmjs.com open_in_newDefine runtime schemas and infer TypeScript types from them
zod.dev open_in_new3 of 3 replacements have a usable free tier.
