About JSON Validator
JSON Validator checks whether your JSON is valid. Paste it and the result appears as you type; if the JSON is invalid you see the parser’s error message so you can find the problem, such as a missing comma, quote or bracket. It runs in your browser.
How to use JSON Validator
- Paste your JSON.
- It is checked automatically.
- Read the result or the error message and fix the JSON.
When JSON Validator is useful
- Check an API response or config file
- Find a syntax error in hand-written JSON
- Confirm data is valid before importing it
Frequently asked questions
How do I check whether JSON is valid?
Paste it into the validator above. It tells you if the JSON is valid and shows the error message if it is not.
What are the most common JSON mistakes?
Trailing commas, single quotes instead of double quotes, unquoted keys and missing brackets are the usual causes.
Is JSON Validator free?
Yes. You can use Modyfiles tools for free, and you do not need an account for your first 10 files. A paid plan raises the daily limits and the maximum file size.
Do I need to install anything to use JSON Validator?
No. It works in your web browser on desktop and mobile, so there is nothing to download or install.
Is my data sent to a server?
This tool runs in your browser, so the text or data you enter is processed on your device.
What else can Modyfiles do besides JSON Validator?
Modyfiles has more than 85 free tools for PDFs, images, audio, developers and text in one place. See the related developer tools below, or browse every tool from the tools page.
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