JSON to TypeScript Converter – Paste JSON, Get Interfaces
If you work with APIs or JSON data regularly, you’ve probably written TypeScript interfaces by hand more times than you’d like. I built a tool to cut that step out: JSON to TypeScript Converter.
It does one thing: you paste JSON, and it gives you clean, typed TypeScript interfaces. That’s it. No account needed. No tracking. Just a straightforward utility that saves time.
You can use it here:
👉 https://tool-json-to-typescript-converter.vercel.app
It handles nested objects, arrays, optional fields (based on null values), and basic type inference. You’ll get interfaces with proper string, number, boolean, and null types. If your JSON has arrays with mixed types or inconsistent shapes, it warns you — because those are the kinds of edge cases that cause bugs later.
There’s a free tier that covers most use cases. You can convert up to 5 JSON snippets per session, and the output includes basic interfaces with readable formatting.
If you use this regularly, there’s a Pro tier for $9/month. It adds:
- Unlimited conversions
- Export as
.tsfile - Support for union types in arrays
- Nullable field detection (via comments or
| null) - Dark mode (because not everyone codes in the light)
No credit card required to try the free version. The Pro tier uses Stripe — you pay directly, no middleman.
I built this because I kept doing the same thing across projects: parsing API responses and manually writing interfaces. Even with good IDEs, it’s repetitive. This isn’t meant to replace type safety or runtime validation — it’s just a helper to get you started faster.
It’s open-source (frontend only, for now), and I welcome feedback or issues on the GitHub repo (linked on the site).
Try it next time you’re staring at a JSON response and dreading the typing. Might save you 10 minutes — and a few typos.
Top comments (0)