Schema validation

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, as measured by Bundlephobia. "-" means the value has not been fetched.

• nvmrccommand-line tool to validate a `.nvmrc` file
• page-agent-sdkAI agent SDK for web pages — embed a chat assistant that edits page data via schema-validated tools. A lighter, framework-agnostic alternative to CopilotKit/LangChain for in-page JSON-editing agents. Vue-bundled; works with DeepSeek, OpenAI, MCP.
• @lens-protocol/metadataLens Protocol Metadata Standards
• tschemaA tiny (500b) utility to build JSON schema types.
• zod-prisma-v4A Prisma generator that creates Zod schemas for all of your models
• @minecraft/bedrock-schemasJSON Schemas and TypeScript types for Minecraft Bedrock Edition content files (entities, blocks, items, biomes, and more).
• zodlineType-safe CLI argument parser powered by Zod schemas. Zero dependencies, inferred TypeScript types, and automatic help generation.
• @swimlane/obfuscatorObfuscate objects based on a JSON Schema
• @openmaic/dslThe MAIC slide DSL: the pure, dependency-free contract (types + JSON Schema + validators + version/migration helpers) that @openmaic/renderer and @openmaic/importer both depend on.
• domain-objectsA simple, convenient way to represent domain objects, leverage domain knowledge, and add runtime validation in your code base.
• validate.io-containsValidates if an array contains an input value.
• indicative-rulesCollection of validation rules for indicative
• express-jsonschemaExpress middleware for jsonschema validation.
• react-structured-dataDeclarative JSON-LD Structured Data for ReactJS Apps
• cottuscustomizable JavaScript data validator
• @lottiefiles/lottie-typesRepresentation of the Lottie JSON Schema in Typescript
• @jarenjs/validateJaren is a JavaScript JSON Schema Validator
• ember-model-validatorember addon. It adds validation support to your Ember-Data models.
• @spinajs/validationvalidation library for spinajs framework
• validate.io-nanValidates if a value is NaN.
• jest-serializer-graphql-schemaJest serializer for GraphQLSchema objects
• jsonv-tsJSON Schema builder and validator for TypeScript with static type inference, Hono middleware for OpenAPI generation and validation, and MCP server/client implementation. Lightweight, dependency-free, and built on Web Standards.
• @servicestack/clientServiceStack's TypeScript library providing convenience utilities in developing web apps. Integrates with ServiceStack's Server features including ServiceClient, Server Events, Error Handling and Validation
• br-validate-dfe-access-keyUm validador de chave de acesso de DFes (Documentos Fiscais eletrônicos)
• @varlock/expo-integrationExpo/React Native Babel plugin to use varlock for .env file loading - adds validation, type-safety, and extra security features
• @glyphjs/schemasZod schemas for Glyph JS components with JSON Schema generation
• zodockA library for generating mock data based on Zod schemas
• validate.io-nan-primitiveValidates if a value is a NaN primitive.
• @zodios/axiosTypescript API client with axios
• @okfetch/fetchA type-safe fetch wrapper with validation, retries, plugins, and streaming.
• @jirutka/ajv-cliCLI for Ajv JSON Schema Validator with human-friendly error messages
• @okfetch/apiA typed API client builder for okfetch based on endpoint schemas.
• grunt-jsvalidateValidate JavaScript source.
• mocker-data-generatorA simplified way to generate mock data, builds using a simple schema and with the FakerJs
• validate-ip-nodeValidate IPv4 and IPv6 addresses.
• ifscThis is part of the IFSC toolset released by Razorpay. You can find more details about the entire release at [ifsc.razorpay.com](https://ifsc.razorpay.com). Includes only a validation library as of now.
• @depup/express-validatorExpress middleware for the validator module. (with updated dependencies)
• joifulTypeScript Declarative Validation. Decorate your class properties to validate them using Joi.
• @nahkies/typescript-koa-runtimeRuntime package for code generated by @nahkies/openapi-code-generator using the typescript-koa template
• ata-validatorJSON Schema validation that compiles for speed and still runs where code generation is blocked. Compiled and interpreted engines answer identically at 100% of the official suite. TypeScript inference, Standard Schema V1, and a build step that emits depend
• @sroussey/json-schema-to-tsInfer typescript types from your JSON schemas!
• better-validatorSecond generation object or request validator for node.js
• core-zod-schema-validatorLightweight package for API testing to validate API responses against ZOD schemas. It can be used directly in any project.
• @shexjs/visitorShape Expressions Visitor and schema index generator.
• @shexjs/parserShape Expressions Compact Syntax (ShExC) parser.
• @amqp-contract/contractContract builder for amqp-contract
• vat-validationCheck the validity of a VAT number
• social-linksValidate & sanitize social links
• ibantools-germanyIBAN Validator and Generator for German Bank Accounts
• fastify-no-additional-propertiesAdd `additionalProperties: false` by default to your JSON Schemas

• valibot vs zod
• @asteasolutions/zod-to-openapi vs zod-openapi
• @hey-api/openapi-ts vs zod-openapi
• @hey-api/openapi-ts vs @asteasolutions/zod-to-openapi
• convict vs envalid
• type-graphql vs quicktype-core
• io-ts vs runtypes
• json-schema-to-typescript vs ts-json-schema-generator
• valibot vs superstruct
• @standard-schema/spec vs json-schema-to-ts
• @standard-schema/spec vs runtypes
• typebox vs ts-json-schema-generator
• @standard-schema/spec vs io-ts
• superstruct vs express-validator
• @apidevtools/swagger-parser vs @zodios/core
• json-schema-to-ts vs runtypes
• effect vs json-schema-to-ts
• graphql-scalars vs graphql-query-complexity
• joi vs v8n
• json-schema-to-ts vs io-ts