If you want a JSON formatter online, free and with nothing to install, open AyeTab's JSON Formatter in any browser tab and paste. It indents the JSON, checks it for errors and can squeeze it back into one line, all inside the page.
Who needs a formatter that runs in a tab
You do not have to be a backend engineer to run into JSON. It shows up wherever software stores settings or data in plain text:
- Browser game and web projects. Level data, sprite sheet maps and save files are often JSON.
- Mods and config files. Many apps and tools keep their settings in a JSON file you can edit by hand.
- School and side projects. Public APIs return JSON, and the first thing you want is to see its shape.
- Shared machines. On a library or school computer you usually cannot install an editor or an extension.
In all of these, a tool that works in a plain browser tab is the easiest fix. There is nothing to download, nothing to set up and no account to create.
How to use it
- Open app.ayetab.com/tools/json-formatter in Chrome, Firefox, Edge or Safari.
- Paste your JSON. The page formats it and checks it as you paste.
- If there is a mistake, look at the error and fix that spot. Typical ones are a comma after the last item or a key without double quotes.
- Copy the tidy version, or press Minify for a single line.
- Press Clear when you are done.
A status line shows how many lines and bytes the JSON has, which helps when a config file has a size limit.
What free means here
Plenty of free tools come with a catch: a signup wall, a watermark or a nudge to upgrade. The AyeTab formatter is free to use with no signup and no watermark on the output. AyeTab is free overall, including its Chrome extension.
The other thing to know is where your text goes. The formatter parses the JSON in your browser, and the input is not uploaded to AyeTab's servers. After the page has loaded it keeps working even if your connection drops. For a save file or a config with personal details in it, that is a sensible default.
Free options compared
| Option | Install needed | Account needed | Where the text is processed |
|---|---|---|---|
| AyeTab JSON Formatter | No | No | In your browser |
| AyeTab Chrome extension | Yes, from the Chrome Web Store | No | In your browser |
| JSONLint | No | No | Website |
| A code editor such as VS Code | Yes | No | On your computer |
If you format JSON often on your own computer, the AyeTab extension for Chrome puts the same formatter on your new tab page, next to other small tools like a Base64 decoder and a JSON to CSV converter.
When another tool is a better fit
If you are already working in a code editor, its built-in format command saves a copy and paste. If you want to explore a large file as a collapsible tree, a site such as jsonformatter.org has a tree view. For a quick paste and fix in any browser, the AyeTab tool is the simplest place to start.