Online JSON Formatter — Prettify with Custom Indentation
Format minified or messy JSON with readable indentation. Choose 2 or 4 spaces or tabs — all processing stays local in your browser.
Developer notes
• Input is validated before formatting — fix syntax errors first. • Indent size and character (spaces vs tabs) apply on each Format action. • Data fidelity is preserved: numbers, key order and string contents stay identical. • For byte reduction, use the JSON minifier — this page targets readability, not compression.
When teams pick this route
• Review minified API logs or webhook payloads during incident response. • Normalize fixtures before opening pull requests. • Prepare readable snippets for documentation or Slack threads. • Inspect converter output before exporting to YAML or CSV.
Worked examples
Minified log line
Sample input
Formatted output
Nested config with tabs
Sample input
Formatted output
Navigate related JSON tools
Validate first with the JSON validator, spot regressions using JSON diff, or explore keys in the JSON tree viewer. Tighten payloads via our JSON minifier or export through JSON → XML.
JSON formatter FAQ
Beautify without changing data
Does formatting change values?
No — only whitespace and indentation change. Parsed data remains identical.
Difference vs JSON minifier?
The minifier removes whitespace to shrink file size. This formatter adds indentation for human review.
Key order?
Insertion order from the parser is preserved in the formatted output.
Server uploads?
No — formatting executes locally in your browser.
Can I sort keys?
Not on this page — use the JSON minifier options if you need deterministic key sorting before compression.
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