API Response Formatter
Paste any raw API response. Auto-detects JSON or XML and prettifies for readability. Everything runs in your browser.
About API Response Formatter
The API Response Formatter auto-detects whether a pasted response body is JSON, XML or plain text, then pretty-prints it with syntax highlighting. One paste — no switching between separate formatters.
Auto-detection is convenient when a response comes from logs, a browser network panel or a command-line request without a trustworthy content-type header. Structural errors are reported so truncated JSON and malformed XML can be distinguished from valid but unexpected data.
Processing is client-side, so production responses containing tokens or user data stay on your machine. That makes the formatter a safer default than pasting live payloads into anonymous public pastebins while debugging an incident.
When auto-detect is unsure, force JSON or XML explicitly. A body that starts with whitespace, a BOM or an HTML error page can otherwise look like “plain text” even though you expected structured data.
How API Response Formatter works in practice
- 1Paste the raw response body into the input area.
- 2Let the tool auto-detect the type, or force one with the dropdown.
- 3Adjust indentation, then copy or download the formatted output.
- 4If parsing fails, use the structural error message to locate truncation or a missing bracket before retrying.
Jobs this tool is built for
- Pretty-print a compressed JSON response copied from a browser network panel.
- Inspect XML returned by a legacy SOAP or integration endpoint.
- Identify a truncated or structurally invalid response captured in application logs.
- Download a readable response body for an issue report without changing its data.
What you can do here
- Auto-detection of JSON and XML
- Syntax highlighting on the output
- Reports common structural errors
- Configurable indentation
- Copy and download buttons
Limits and honest caveats
- Formatting does not redact secrets. Remove access tokens, credentials and unnecessary personal data before sharing the formatted result.
- Very large bodies depend on available browser memory and may make syntax highlighting slower even when parsing succeeds.
- This tool formats an existing body — it does not send HTTP requests. Use the API Tester when you need to call an endpoint.
Common questions about API Response Formatter
What formats are supported?
JSON, XML and plain text.
Can it handle very large responses?
Yes — multi-megabyte payloads work on desktop browsers.
What happens if auto-detection chooses the wrong type?
Use the format dropdown to force JSON, XML or plain text, then format again.
Does it send a request to an API?
No. This tool formats an existing response body. Use the API Tester when you need to make the HTTP request itself.
Does formatting change the response values?
It changes presentation and indentation, not the parsed JSON or XML values. Plain text is displayed as supplied.
This page was written by the ToolSink team to explain how API Response Formatter works on this site — it is not syndicated, scraped, or spun from another publisher. How we write tool guides · Site updates · About ToolSink.
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