validator.js vs Zod
Which should you use? A side-by-side look at what each one does, who it suits, what it costs, how hard it is to set up, and where each falls short.
Open source · MIT
A JavaScript library for checking and cleaning up strings, like emails, dates, and URLs.
Open source · MIT
TypeScript-first library for validating data at runtime and inferring static types from the same schema.
The short answer
Choose validator.js if you need…
- JavaScript developers validating form or API input on Node.js
- Developers who need checks like isEmail or isDate without writing regular expressions themselves
- Projects that want to import only the individual validators they use
- Browser projects that load a standalone script or CDN file
Choose Zod if you need…
- TypeScript developers who want runtime checks that match their static types
- Teams validating API request or response data in TypeScript projects
- Developers who want one schema definition instead of separate types and validators
Side-by-side
| validator.js | Zod | |
|---|---|---|
| Type | Library | Library |
| Price | Free and open source | Free and open source |
| Licence | MIT | MIT |
| GitHub stars | 23.7k | 44.2k |
| Setup difficulty | Beginner | Beginner |
| How you get it | Install with a package manager | Install with a package manager |
| Main language | JavaScript | TypeScript |
| Last code update | 56 days ago | 7 days ago |
What each one is
validator.js
validator.js is a JavaScript library that provides many functions for checking whether a string matches a format, such as an email address, a date, or a credit card number, and for sanitizing strings. It is installed through npm and can be used on a server or in a browser. The README states it only works on strings, so other input must be converted to a string first.
Zod
Zod is a TypeScript library for defining schemas that check whether data has the expected shape, such as form input or API responses. You describe the shape once, and Zod both validates values at runtime and gives you a TypeScript type that matches it. The README provided is truncated and only points to the package, so details beyond that are limited here.
Best for
validator.js
- JavaScript developers validating form or API input on Node.js
- Developers who need checks like isEmail or isDate without writing regular expressions themselves
- Projects that want to import only the individual validators they use
- Browser projects that load a standalone script or CDN file
Zod
- TypeScript developers who want runtime checks that match their static types
- Teams validating API request or response data in TypeScript projects
- Developers who want one schema definition instead of separate types and validators
Strengths
validator.js
- Covers a wide range of common string checks in one package
- Lets you import only the validators you need to keep bundles smaller
- Works in both server-side Node.js code and in the browser
Zod
- Schemas produce both runtime validation and static type inference
- MIT licensed and widely starred (about 44k stars at time of metadata)
- Actively maintained, with a recent release (v4.6.7) and a recent push
Not ideal for
validator.js
- Anyone who needs validation of non-string data such as numbers or objects, since the README says non-string input causes an error
- Non-JavaScript projects, since the library is written for JavaScript and npm
- Non-developers, since it is a code library with no interface
Zod
- Projects not using TypeScript, since the library is described as TypeScript-first and the README excerpt gives no JavaScript-only guidance
- Readers needing a no-code tool, because this is a code library that requires writing schemas
Trade-offs
validator.js
- Accepts only strings, so inputs must be converted before checking
- The README excerpt does not show how strict each check is, so results should be tested against your own rules
Zod
- The README excerpt was truncated, so API details and setup specifics could not be verified here
- Being TypeScript-first means its main value depends on using TypeScript
Getting started
Zod
Clone the repository
git clone https://github.com/colinhacks/zodFrequently asked questions
What is the difference between validator.js and Zod?
validator.js: A JavaScript library for checking and cleaning up strings, like emails, dates, and URLs. Zod: TypeScript-first library for validating data at runtime and inferring static types from the same schema. validator.js suits javascript developers validating form or api input on node.js, while Zod suits typescript developers who want runtime checks that match their static types.
Are validator.js and Zod free?
validator.js: Free and open source. Zod: Free and open source.
Is validator.js or Zod more popular?
Zod has more GitHub stars (44.2k) than validator.js (23.7k). Popularity isn't the same as fit — check which one matches your use case above.
What are other alternatives to validator.js and Zod?
Other options people compare them with include Yup, VeeValidate, class-validator, Eureka, ts-pattern.
Keep comparing
Built from our catalogue entries for both products: open-source details come from each project's README (AI-assisted, refreshed weekly) and GitHub data; AI-tool details are editorial. Spotted something wrong? Let us know from either product's page.