JSON Validator
How to Use
Follow these simple steps to get started instantly — no signup required.
Paste your JSON
Drop in any JSON — an API response, a dataLayer object, a config file.
Validate
Click validate to check syntax against the JSON specification.
Read the error
If invalid, the exact parser error tells you what is wrong and where.
Copy formatted output
Valid JSON is pretty-printed with consistent indentation, ready to copy.
Validate JSON without sending it anywhere
JSON payloads often contain exactly the data you should not paste into random websites: API keys, customer records, internal endpoints. This validator runs 100% client-side — the JSON never leaves your browser tab, which makes it safe for the payloads you actually work with.
For marketers and analysts, that includes dataLayer objects, GTM container exports, and analytics API responses — all of which are JSON, and all of which break silently when malformed.
The errors that break tracking implementations
A trailing comma in a dataLayer push, a single-quoted key in an ecommerce items array, an unescaped quote inside a product name — each produces JavaScript errors that stop your tracking silently. The page works, the analytics don't.
Validating the JSON structure before deployment catches these in seconds instead of discovering them in next week's reports.
Format for humans, minify-proof for machines
Pretty-printed output with consistent indentation makes nested structures reviewable in pull requests and readable in documentation. Paste minified API output, get structured JSON you can actually reason about.