Video guide · 17 seconds
Watch: format and validate JSON
No sound. Each step is captioned on screen and also written out in the guide below.
Data & developer tools JSON
JSON Formatter & Validator
Make messy JSON readable, check it for errors, and keep your data on your device.
Workspace
Paste JSON to get started
Runs locally in your browser. Your JSON is not uploaded, saved, or included in sharing.
Or drop one .json or .txt file here (up to 5 MiB). Replaces this input; stays on your device.
JSON objects, arrays, and primitives are supported.
Formatted JSON
Your formatted JSON will appear here.
A quick guide
How it works
- 01Paste
Add an object, array, or JSON value to the input panel.
- 02Check
Validate catches syntax issues before you share or ship it.
- 03Format
Choose an indentation style and copy or download the result.
Example
Valid JSON is delightfully strict
{
"tool": "BytesBench",
"private": true
}Use double quotes around keys and text. JSON does not allow comments or trailing commas.
Good to know
Frequently asked questions
Is my JSON sent anywhere?
No. Formatting and validation happen in this page’s browser session. BytesBench does not save the content or put it in a share link.
Why is my JSON invalid?
The most common causes are single quotes, a missing comma or colon, an unclosed bracket, or a trailing comma. The validation message points you toward the likely fix.
What happens with duplicate keys?
JSON permits the text, but parsers generally keep the last value for a repeated key. Avoid duplicates when every value matters.