io-ts alternatives
8 packages that do the same job as io-ts: runtypes, @standard-schema/spec, json-schema-to-ts, @accordproject/concerto-vocabulary, @inixiative/json-rules, json-schema-to-typescript-lite, @c15t/schema, @ankhorage/contracts. Figures below are from npm, GitHub and Bundlephobia.
| Package | Weekly downloads | 12-month change | Gzip | Dependencies | Last release | Module | Types | Runtimes |
|---|---|---|---|---|---|---|---|---|
| io-ts This package | 2m | +22% | - | 0 | 1 year ago | ESM + CommonJS | Bundled | - |
| runtypes | 186.3k | -1% | - | 0 | 1 month ago | ESM + CommonJS | Bundled | - |
| @standard-schema/spec | 80.7m | +892% | - | 0 | 9 months ago | ESM + CommonJS | Bundled | - |
| json-schema-to-ts | 24.9m | +962% | - | 2 | 2 years ago | ESM + CommonJS | Bundled | - |
| @accordproject/concerto-vocabulary | 58.5k | - | - | 2 | 16 days ago | ESM + CommonJS | Bundled | - |
| @inixiative/json-rules | 21.6k | - | - | 2 | 4 days ago | ESM + CommonJS | Bundled | - |
| json-schema-to-typescript-lite | 629.1k | +139% | - | 2 | 1 year ago | ESM + CommonJS | Bundled | - |
| @c15t/schema | 116.6k | - | - | 1 | 1 month ago | ESM + CommonJS | Bundled | - |
| @ankhorage/contracts | 33.8k | - | - | 2 | 1 day ago | ESM only | Bundled | - |
12-month change compares the average of the last 4 weeks of downloads with the first 4 weeks of the 52-week series. Gzip size is for the whole package (Bundlephobia). Runtimes are taken from each package's own documentation; "-" means not recorded.
Runtime validation for static types
Compared with io-ts
- 11x fewer weekly downloads (186.3k vs 2m)
- Last release 14 Aug 2026 vs 10 Dec 2024
- 2.5x fewer GitHub stars (2.7k vs 6.8k)
A family of specs for interoperable TypeScript
Compared with io-ts
- 39x more weekly downloads (80.7m vs 2m)
- Last release 15 Dec 2025 vs 10 Dec 2024
- 1.9x fewer GitHub stars (3.6k vs 6.8k)
Infer typescript types from your JSON schemas!
Compared with io-ts
- 12x more weekly downloads (24.9m vs 2m)
- 2 dependencies vs 0
- Declares Node.js >=16 vs none declared
- Last release 29 Aug 2024 vs 10 Dec 2024
- 3.8x fewer GitHub stars (1.8k vs 6.8k)
Associate human-readable text to model declarations
Compared with io-ts
- 35x fewer weekly downloads (58.5k vs 2m)
- 2 dependencies vs 0
- Declares Node.js >=18 vs none declared
- Last release 8 Sept 2026 vs 10 Dec 2024
- 33x fewer GitHub stars (208 vs 6.8k)
TypeScript-first JSON rules engine with intuitive syntax and detailed error messages
Compared with io-ts
- 95x fewer weekly downloads (21.6k vs 2m)
- 2 dependencies vs 0
- Last release 20 Sept 2026 vs 10 Dec 2024
- 1363x fewer GitHub stars (5 vs 6.8k)
Lite version of json-schema-to-typescript
Compared with io-ts
- 3.3x fewer weekly downloads (629.1k vs 2m)
- 2 dependencies vs 0
- Last release 24 Jul 2025 vs 10 Dec 2024
- 2.0x fewer GitHub stars (3.3k vs 6.8k)
Framework-agnostic Valibot schemas and TypeScript types for c15t consent management
Compared with io-ts
- 18x fewer weekly downloads (116.6k vs 2m)
- 1 dependency vs 0
- Last release 4 Aug 2026 vs 10 Dec 2024
- 3.6x fewer GitHub stars (1.9k vs 6.8k)
Serializable app, action, theme, auth, and secret-store contracts for Ankhorage.
Compared with io-ts
- 61x fewer weekly downloads (33.8k vs 2m)
- 2 dependencies vs 0
- ESM only vs ESM + CommonJS
- Last release 23 Sept 2026 vs 10 Dec 2024
- 6815x fewer GitHub stars (1 vs 6.8k)
Indexability: Indexed.