Validate JSON
any languageValidateCheck whether the input is valid JSON; returns {"valid":true|false}.
0/500000Drop .txt, .html, .md, .csv, or .json files here.
Output appears here after you run the tool.
Max input 500000 chars · Worker timeout 2s · Offline runtime
About this tool
Validate JSON: Check whether the input is valid JSON; returns {"valid":true|false}.
Use cases
- Check whether text matches the rules behind “Validate JSON”
- Smoke-test pasted content before form submit or ingest
- Spot format issues in logs or config snippets
- Spot-check consistency across sample rows
How to use it
- Paste text into Input, or drop a .txt / .html / .md file.
- Click Run, or wait for auto-run to finish.
- Copy the Output; use “Use example” for a quick trial.
Notes
- Everything runs in your browser; your text is never uploaded to a server.
- Deterministic transform: the same input and options always yield the same output—no AI rewrite.
- Keep a single run within the tool limit (about 500000 characters); larger payloads may time out.
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