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GigaJSON

JSON Validator

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Check whether text is valid JSON. An error comes with its line, its column and what the parser expected there. Most mistakes can be fixed with "Repair".

How to use it

  1. Paste JSON or open a file.
  2. The result updates as you type: "Valid JSON" with a summary, or the first error and where it is.
  3. Use "Repair" to fix common mistakes, then copy or download the corrected JSON.

Read more: How to fix invalid JSON: the 10 most common errors

Private, and made for big files

This tool runs in your browser, in a background worker: nothing you paste or open is uploaded, and nothing is kept after you leave. JSON and XML input can be up to 1 GB, depending on available memory. Processing runs in a background worker; large analyses can take a minute or more. If your connection drops while you're here, the tool keeps working. When one tool isn't enough, GigaJSON opens your data with a tree, a table, JSONPath/JMESPath/jq queries, transforms, diff and history.

Questions

What makes JSON invalid?

Usually single quotes instead of double quotes, keys without quotes, trailing commas, comments, a missing comma or bracket, or values like NaN, undefined or Python's True and None.

Is my data uploaded?

No. The tool runs in your browser, in a background worker. Nothing you paste or open goes to a server, and nothing is kept after you leave the page.

How large a file can it handle?

JSON and XML input can be up to 1 GB, depending on memory. CSV/YAML input and JSON repair are limited to 128 MB. Validation runs in a background worker. jq, text editing and text-based exports have separate limits, shown when you use them.

Does it validate against a JSON Schema?

This page checks syntax only. To check data against a schema, open it in GigaJSON and use Types, then Validate.

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