Edit JSON online in the browser with live validation, formatting, sort keys, tree view, and instant error feedback. Upload a file or paste your JSON, make changes, then copy or download the result. Everything runs 100% client-side, so your data never leaves your device.
100% client sideInstant resultNo data sent
Input JSON
Output
Paste JSON to format, beautify, validate, minify, analyze, or view it as a tree.
0 input chars0 output charsWaiting for valid JSON
Frequently asked questions
4 answers
Yes. Paste your JSON or upload a file, make your changes in the editor, and then copy the result or download it as a file. Nothing is installed and nothing is uploaded to a server: the whole editing session happens in your browser tab, which makes it a quick alternative to opening an IDE for a one-off config change.
Yes. The editor parses your JSON continuously and gives instant feedback: valid input is confirmed immediately, and any syntax error is flagged with a clear message showing the line and position of the problem. You see mistakes the moment you make them instead of discovering them later when an application rejects the file.
Yes. The editor can automatically repair the most common issues, including trailing commas after the last item and single quotes used instead of double quotes. These are the mistakes that creep in when JSON is written by hand or copied from JavaScript code, and fixing them automatically saves you from hunting down each one manually.
There is no fixed upload cap because nothing is uploaded: the limit is your browser's memory. Files of several megabytes edit smoothly on a typical machine, and the collapsible tree view keeps navigation fast even with thousands of nested nodes. For extremely large files (hundreds of megabytes), performance depends on your hardware, since the whole document is parsed in memory.
Sometimes you just need to tweak one value in a config file, fix a broken API payload, or reshape a test fixture, and opening a full IDE is overkill. This JSON editor online tool covers that workflow end to end: paste or upload your JSON, edit it with continuous validation catching every syntax slip as you type, reformat with your preferred indentation, sort keys alphabetically, and check the result in tree view before copying or downloading the file. Common mistakes like trailing commas and single quotes can be repaired automatically. Because the editor is free and runs entirely in your browser, credentials, tokens, and customer data in your files never touch a server.