JSON Tools
A complete set of free online JSON tools for developers — format, validate, diff, query and convert JSON entirely in your browser. Every tool runs client-side, so your payloads never leave this page.
29 free json tools — all browser-based
JSON Formatter
Formats and beautifies JSON data for better readability. It ensures proper indentation and structure, making it easier to analyze and debug..
JSON Minifier
Compresses JSON by removing all whitespace and indentation into a single-line minified document, with live validation, a before-and-after byte size comparison, and a one-click copy.
JSON Diff
Compares two JSON documents side by side and lists every added, removed, and changed key with its full path, useful for reviewing API response or config changes..
JSON Path Finder
Queries a JSON document with a simplified path syntax ($.key, [index], [*], .*) and shows every matching value, useful for exploring large API responses..
JSON Pointer Extractor (RFC 6901)
Extracts values from a JSON document using RFC 6901 JSON Pointer references (e.g. /foo/0/bar) with support for escaped slashes (~1) and tildes (~0), plus a batch mode that evaluates multiple pointers at once, useful for debugging JSON Patch operations, testing OpenAPI / JSON Schema $ref resolution, and pulling nested fields from large API responses..
JSON Schema Validator
Validates a JSON document against a JSON Schema (draft-07) in real time, listing every validation error with its path when the data doesn't conform..
JSON5 Formatter
Formats and validates JSON5 (JSON with comments, trailing commas, unquoted keys, single quotes, hex numbers, Infinity, and NaN) into indented output with syntax error reporting.
JSON-LD Generator (Schema.org)
Builds schema.org JSON-LD structured-data blocks (WebSite, Organization, BreadcrumbList, FAQPage, Article, Product, LocalBusiness, and Event) with a live JSON preview and copy-ready script tag, useful for wiring up rich results / rich snippets in Google Search, validating structured data ahead of the Rich Results Test, and adding semantic metadata to Next.js, WordPress, and static sites..
JavaScript Object to JSON
Converts JavaScript objects into a properly formatted JSON string. Ensures compatibility with APIs, storage, and data exchange processes..
JSON CSV Converter
Converts JSON arrays of objects into CSV files, and CSV files back into JSON, with support for quoted fields containing commas, quotes, and newlines..
JSON to YAML Converter
Converts JSON into clean, human-readable YAML 1.2 with consistent indentation and optional flow-style handling.
JSON to TypeScript
Infers TypeScript interfaces from a JSON object, automatically generating nested interfaces for embedded objects and arrays..
JSON to Rust Converter
Converts JSON into Rust struct definitions with serde derive macros (Serialize, Deserialize) and inferred types (String, i64, f64, bool, Option, Vec, and nested structs), useful for generating serde-compatible models for Rust HTTP clients and services from a sample JSON payload..
JSON to Go Struct Converter
Converts JSON into Go struct definitions with json struct tags, inferring field types (string, int, float64, bool, nested structs, and []T slices) from the data and capitalizing exported field names.
JSON to Java Class Converter
Converts JSON into Java POJO class definitions with camelCase fields, getters, and setters, inferring String, Integer, Double, Boolean, and nested class types.
JSON to Python Converter
Converts JSON into Python dataclass or TypedDict definitions with inferred types (str, int, float, bool, Optional, List, and nested dataclasses), plus a ready-to-use literal, useful for building Pydantic and dataclass models from a sample JSON payload in FastAPI and other Python services..
JSON to PHP Converter
Converts JSON into PHP associative array or class definitions with inferred types (string, int, float, bool, nested arrays, and nested classes), with PHP 7+ typed properties and json_decode-compatible output, useful for pasting sample JSON into Laravel and Symfony projects and generating API response DTOs without scaffolding..
JSON to C# Class Converter
Converts JSON into C# class definitions with PascalCase properties and inferred types (string, int, double, bool, DateTime, nested classes, and List<T>), ready to paste into a .NET project.
JSON to SQL Converter
Converts a JSON array of objects into SQL INSERT statements for a target table, or a single JSON object into a CREATE TABLE statement with inferred column types.
JSON to Kotlin Data Class
Generates Kotlin data classes from a JSON sample with kotlinx.serialization annotations, choosing Int or Long by magnitude, Double for decimals, nullable types with defaults for JSON nulls, and adding @SerialName only when the camelCase property differs from the wire key, while reusing one class for repeated object shapes..
JSON to Swift Codable
Generates Swift Codable models from a JSON sample as structs or final classes, mapping JSON types to Int, Double, Bool, String and arrays, emitting a CodingKeys enum only when a wire key differs from the lowerCamelCase property, backtick-escaping Swift reserved words, and reusing one model for repeated object shapes..
JSON to Dart Model (Flutter)
Generates null-safe Dart model classes from a JSON sample with hand-written fromJson and toJson methods, so Flutter projects need no build_runner step, decoding list elements through their own model, widening ints to double where the JSON shows decimals, and offering immutable final fields with a const constructor..
JSON to Zod Schema
Generates a Zod schema and its inferred TypeScript type from a JSON sample, mapping objects to z.object, arrays to z.array, integers to z.number().int(), and promoting recognizable strings to z.string().email(), .url(), .uuid() and .datetime() refinements, useful for validating API responses, tRPC inputs and form payloads at runtime..
JSON to Pydantic Model
Generates Pydantic v2 BaseModel classes from a JSON sample, mapping types to int, float, bool, str, list and nested models, adding Field(alias=...) with populate_by_name when a key is not a valid Python identifier or is not snake_case, using Optional with a None default for nulls, and emitting classes in dependency order so the file imports cleanly..
JSON to Scala Case Class
Generates Scala 3 case classes from a JSON sample with Int, Long, Double, Boolean and String inference, Option[T] for nulls, List[T] for arrays and nested case classes for objects, plus an optional circe Decoder/Encoder derivation block, useful for modelling API payloads in Play, Akka HTTP and Spark jobs..
JSON to JSDoc Typedef
Generates JSDoc @typedef blocks from a JSON sample so plain JavaScript files get editor autocomplete and tsc --checkJs type safety without migrating to TypeScript, inferring number, string, boolean, array and nested object typedefs, quoting keys that are not valid identifiers, and marking null-valued properties as nullable..
JSON to Mongoose Schema
Generates a Mongoose schema and model from a JSON sample, mapping values to String, Number, Boolean, Date and nested subdocuments, recognizing 24-character hex strings as ObjectId references and ISO-8601 strings as Date, wrapping arrays in [] and adding timestamps, useful for bootstrapping MongoDB collections from an example document..
JSON to NDJSON Converter
Converts between a JSON array and NDJSON / JSON Lines in both directions, emitting one compact JSON document per line for streaming ingestion or parsing a JSONL file back into a pretty-printed array, reporting the offending line number when a record fails to parse, useful for BigQuery and Elasticsearch bulk loads, log pipelines and LLM fine-tuning datasets..
JSON Schema to TypeScript
Converts a JSON Schema document into TypeScript interfaces and types, resolving local $ref pointers into named types, turning enum into a string-literal union, oneOf and anyOf into unions, allOf into an intersection, marking properties absent from required as optional, and mapping additionalProperties to an index signature..
How to format and validate JSON
Paste your raw JSON into the JSON Formatter and press Format to get pretty-printed, indented output with syntax error reporting.
Use the JSON Schema Validator to check that a payload conforms to a Draft 2020-12 schema — handy for API contract testing.
The JSON Diff tool highlights added, removed and changed keys between two documents, ideal for debugging API responses across environments.
Querying JSON with JSONPath and JSON Pointer
JSONPath (RFC 9535) uses expressions like $.users[*].name to select nodes; the JSON Path Finder evaluates these against your document.
JSON Pointer (RFC 6901) targets a single node with a slash path like /users/0/name — use the JSON Pointer Extractor for batch extraction.
Converting JSON to code and other formats
Generate typed interfaces from sample payloads with JSON to TypeScript, or Rust structs with JSON to Rust — great for scaffolding API clients.
Round-trip between JSON, YAML, CSV and JSON5 using the dedicated converters without leaving your browser.
Frequently asked questions
Are these JSON tools free?
Yes. Every JSON tool here is completely free, requires no signup, and runs entirely in your browser.
Do the JSON tools upload my data?
No. All parsing and formatting happens client-side in JavaScript, so your JSON payloads never leave this page.
Which JSON standard do the tools support?
The formatter and validator follow RFC 8259. The schema validator targets JSON Schema Draft 2020-12, and JSON5 support covers the JSON5 spec.