About JSON Editor Pro

JSON Editor Prois a free, browser-based workspace for editing, formatting, comparing, and converting JSON — plus a growing set of adjacent developer utilities (JWTs, encoders, regex, timestamps, and more). It’s built by Nivo Apps.

Why it exists

Most online JSON tools quietly upload whatever you paste in to a server. For API responses, config files, and other data that often contains real user information, that’s a bad default. JSON Editor Proruns entirely client-side: parsing, validation, formatting, diffing, and every conversion happen in your browser’s JavaScript engine. Your documents are stored locally on your device (IndexedDB, with a localStorage-safe fallback) and are never transmitted to us or anyone else.

What’s included

  • A full JSON editor with tree, code, form, and preview views, multi-tab workspaces, and a structural diff/compare engine.
  • Single-purpose tools for formatting, validating, minifying, and generating a schema from JSON.
  • Converters between JSON and YAML, XML, CSV, and TOML.
  • Developer utilities: JWT decode/generate, Base64 and URL encode/decode, UUID generation, a regex tester, a timestamp converter, and an HTTP status code reference.
  • Written guides that go deeper on specific JSON topics than a tool’s UI alone can.

See the full, current list on the all tools page.

How it’s funded

JSON Editor Prois free to use, with no account required. It is supported by advertising and optional reader donations, which cover hosting and ongoing development. Using an ad blocker doesn’t change what you can do with the tools.

Questions or feedback

Use the in-app feedback button, or see the Contact page. Read our Privacy Policy for details on what little data is collected and how it’s used.