Debugging an API response
Pasting the raw response and formatting it is the first step to understanding what a service returns.
JSON formatter
Format and validate JSON, with error detection.
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What it is for
JSON is the format almost all data travels in between applications today. It is human-readable, but when transmitted it usually arrives on a single line with no spaces, to save bytes, and in that state it is practically impossible to follow.
Formatting restores the indentation and line breaks that reveal its structure: what sits inside what, where each object begins, which elements each list holds. With a JSON of any size, the difference between seeing it formatted or not is the difference between understanding it in ten seconds and not understanding it at all.
The tool also validates the syntax. If the text is not correct JSON, it shows the specific error, which is usually exactly what you need: a trailing comma at the end of a list, an unclosed quote, or single quotes where the standard demands double ones.
How it works
- Paste your JSON, even if it's all on one line and hard to read.
- Click "Process": the tool validates the syntax and applies automatic indentation.
- Copy the nicely formatted result, or check the error message if the JSON isn't valid.
When to use it
Finding syntax errors
When a configuration file will not load, validation points to the exact spot.
Reviewing configuration
Many programs store settings in JSON. Formatting lets you review and edit it without breaking it.
Practical tips
- The commonest errors are a trailing comma before a closing bracket and the use of single quotes: JSON allows only double ones.
- JSON does not permit comments. If the file has them, it is not standard JSON however much it looks like it.
- If you are pasting production data, remember it never leaves your browser here, but it is still wise not to leave it on screen.
- For the reverse operation, compacting the JSON, any code editor will strip the line breaks.
Frequently asked questions
What happens if my JSON has a syntax error?
The tool shows you the exact error message so you can pinpoint the problem (an extra comma, an unclosed quote, etc.).
Can it minify JSON instead of formatting it?
This tool is built for readable formatting; for the opposite, any code editor can strip the extra line breaks.