Keep an order ID exact
{"orderId":"9007199254740993","quantity":2}Expected: The order ID remains a quoted string.
Identifiers longer than the safe integer range should not be converted to JavaScript numbers.
JSON Formatter
JSON Formatter
Format, minify, and validate JSON. Make your data easy to read.
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Worked examples: try and compare
These examples show expected results and common failure cases. Loading an example replaces the tool input after confirmation when you already have text.
Find a trailing comma
{"items":[1,2,]}Expected: A syntax error; no downloadable result.
Remove the comma after 2. The corrected array is [1,2].
How to use JSON Formatter
Paste valid JSON, then choose Format or Minify. Invalid syntax produces an error without changing your input. Processing stays on your device.
Check an API response before using it
Paste the JSON body, then choose Format. A response such as {"items":[{"id":7,"active":true}]} becomes easier to inspect without changing its ordinary values. Use Minify when whitespace is unnecessary. Formatting validates JSON syntax; it does not check whether an API returned the fields your application needs.
Fix common parsing failures
JSON requires double quotes around property names and string values. Remove comments and trailing commas; replace single-quoted strings with double-quoted strings. JavaScript objects containing undefined or functions are not JSON. A syntax error can point just after the actual mistake, so inspect the preceding comma or quote too.
Protect large numeric identifiers
This formatter uses JavaScript JSON.parse and JSON.stringify. Integers beyond the safe integer range can lose precision, and repeated object keys do not survive parsing as separate entries. Keep long identifiers in quoted strings and preserve your original input. This is not a lossless editor for arbitrary numeric JSON.
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