Runs in your browser. Your JSON is never uploaded.

Every JSON Tool You Need.

Fast, free, and privacy-first developer utilities. Format, validate, compare, convert, and transform JSON directly in your browser.

Popular:JSON Formatter JSON Diff JWT Decoder JSON to TypeScript JSONPath Explorer

JSON Formatter

Input

Output

Ready. Press Format, Minify, or Validate.

Popular tools

Each tool has its own page, examples, and docs.

Pretty print JSON with 2, 4, or tab indentation and precise error locations.

Strict syntax checks with line and column, plus document statistics.

Compare two documents by path: added, removed, and changed.

JSON Tree Viewer

Expand, search, and copy the JSONPath of any node.

JSONPath Explorer

Live expression matching with highlighted results and match paths.

Convert JSON to clean YAML with proper quoting where it matters.

Code Generation

JSON to TypeScript

Interfaces or type aliases with nested and optional types.

Code Generation

Java 21 records or POJOs with Jackson annotations and optional Lombok.

JSON Schema Generator

Infer a draft 2020-12 schema from example data.

Security & Encoding

Decode header and payload claims locally. Signatures are not verified.

Browse by category

Eight categories, one consistent workspace.

A

JSON Essentials

Formatter, validator, minifier, repair, escape

5 tools

JSON Formatter JSON Validator JSON Minifier

B

JSON Analysis

Diff, merge, tree viewer, JSONPath, flatten

5 tools

JSON Diff JSON Merge JSON Tree Viewer

C

Data Converters

YAML, XML, CSV, TOML in both directions

8 tools

JSON to YAML YAML to JSON JSON to XML

D

Code Generation

TypeScript, Java, Python, Go, C#

5 tools

JSON to TypeScript JSON to Java JSON to Python

E

JSON Schema

Generator, validator, mock data

3 tools

JSON Schema Generator JSON Schema Validator JSON Mock Data Generator

F

Security & Encoding

JWT, Base64, hashes, UUID, URL encoding

5 tools

JWT Decoder Base64 Encode / Decode Hash Generator (SHA)

G

API Developer

API client, cURL converters, webhook tester Webhook tester is blocked: it needs a server.

3 tools

API Client cURL to Fetch cURL to Python

H

More Utilities

Regex, timestamps, cron, text diff, size

5 tools

Regex Tester Unix Timestamp Converter Cron Parser

Your data never leaves the tab.

Parsing, diffing, converting, and code generation all run locally. There is no login, no upload, and no analytics on what you paste.

The few tools that need a server, such as the webhook tester, are labelled before you use them.

Local processing
Inputs stay in memory in your browser tab.
No account
Every core tool works without signing in.
Strict security headers
A tight Content Security Policy and no third-party scripts in tool pages.
Honest labelling
Server-backed tools say so up front, and never run silently.

Why developers use JSON-Utils

Instant on real payloads

Parsing, diffing, and conversion are tuned for large inputs, and large trees render in a virtualized list, so the page stays responsive.

One workspace everywhere

Upload, copy, download, sample, reset, and keyboard shortcuts behave the same in every tool, so you learn the interface once.

Honest about limits

Lossy conversions are flagged before you run them, and one sample is never presented as a complete type definition.

Frequently asked questions

Is my JSON uploaded anywhere?

No. Formatting, validation, diffing, conversion, and code generation run in your browser. Tools that need a server are labelled.

Do I need an account?

No. All core utilities work without login.

Does the JWT decoder verify signatures?

No. It decodes the header and payload only. A decoded token is not a trusted token.

How large an input can I use?

Ordinary files are instant. Very large inputs may take a moment; each tool reports errors honestly rather than pretending to succeed.

Why can the API client fail on some URLs?

Browsers enforce CORS. Requests go directly from your browser and are never silently proxied.