Open a local file or use the input controls.
Files stay on your device
JSON Minifier
Validate and compact JSON without changing large numeric literals, string escapes, duplicate keys, or key order.
Private browser workspaceInput: JSON, text → Output: JSON
⌁
Your file never leaves this browser
Processing happens locally using browser APIs and on-device code. Closing this tab clears the working data.
How it works01 02 03
Done in three simple steps
Paste JSON or open a UTF-8 file, then minify it.
Review the result, then download it.
Frequently asked questions
Does this tool upload my input?+
No. Your input is processed on your device using browser APIs and local code.
Are large numbers rounded?+
No. Validation is separate from whitespace removal. The output retains your original numeric literals instead of parsing and serializing them into rounded JavaScript numbers.
What are the limits?+
5-million-character limit. Only insignificant whitespace outside strings is removed.