Runs locally
JSON Size
UTF-8 byte size of the text you pasted.
Ctrl+Enter runs. Ctrl+Shift+Backspace clears.
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UTF-8 byte size of the text you pasted. Runs in the browser. Nothing is uploaded.
About this tool
Check whether a request body, a webhook payload or a localStorage value fits within its limit. Paste valid JSON and get its exact size in UTF-8 bytes.
How to use it
- 01
Paste the JSON.
- 02
Read its size in bytes.
- 03
Minify it if you need to save space.
FAQ
Frequently asked questions
Does whitespace count?
Yes. The size is measured as pasted; use the JSON Minifier to see the compact size.
What if the JSON is invalid?
Invalid JSON is reported instead of being measured.