Structured data
JSON Minifier
Reduce JSON transfer size while validating the complete document first.
Processed locally. Your input and output are never uploaded.
Tool overview
What JSON minification removes
JSON Minifier parses the document before serializing its data without insignificant spaces or line breaks. Whitespace inside string values is preserved. Size cards compare UTF-8 bytes and show the reduction percentage.
Compact fixtures and transport payloads
- Compact fixtures
- Reduce pasted JSON payloads
- Check whether JSON is already minified
- Measure UTF-8 size savings
Validate before removing syntax whitespace
- Paste or open valid JSON.
- Choose whether non-ASCII characters stay visible or escaped.
- Process and review validation and size statistics.
- Copy or download the minified JSON.
Unicode output and measured byte reduction
- Validation uses the same parser and error format as JSON Formatter.
- Escape Unicode can increase size and is disabled by default.
Remove whitespace outside JSON strings
Before
{
"name": "PasteTidy",
"items": [1, 2]
}After
{"name":"PasteTidy","items":[1,2]}Invalid documents and JavaScript number precision
- Invalid input produces no output.
- Whitespace within quoted strings is never removed.
- Large numeric literals share the browser JSON precision limit.
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Questions
JSON Minifier FAQ
Does minification compress strings?
No. It only removes JSON syntax whitespace outside string values.
Is this gzip compression?
No. The output remains ordinary readable JSON data.