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Format and validate JSON

Validate JSON syntax and add readable indentation without changing the intended data structure.

  1. 1Add files
  2. 2Options
  3. 3Convert
  4. 4Save
No installation · Processed in your browser

Preparing the converter…

Add your JSON filesDrop files here or choose them from your device.Drop here to add your files. Choose JSON files JSONJSONNo fixed byte cap · browser memory and format limits apply
Choose a file to check its format and size.

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Convert CSV to JSONParse a CSV header and rows into JSON records, choosing the input encoding and delimiter.Convert JSON to CSVExport an array of JSON objects as CSV rows, with an option to flatten nested fields.Convert TSV to CSVRead tab-separated records with the selected encoding and write comma-separated CSV.Convert CSV to TSVChange CSV records to a tab-separated file while parsing quoted CSV fields.Convert XML to JSONParse safe XML and represent its elements and values as a JSON structure.

Supported formats and settings

Input formats
JSON
Output formats
JSON
Per-file limit
Current device memory
Total selected-file limit
Estimated by file count and format
Number of selectable files
1–1

Recommended input total: 8 MiB on mobile / 32 MiB on desktop. Low memory can reduce the effective limit.

Your files are not uploaded to a conversion server. A new result is created in your browser.

How to use this tool

  1. Choose files in JSON format. Maximum files per batch: 1.
  2. Review Indentation, then start processing.
  3. Download the JSON result and check its content and quality.

What this tool does

  • Validate JSON syntax and add readable indentation without changing the intended data structure.
  • Read JSON input and save the JSON result as a new file.
  • Available settings: Indentation.

Limitations

  • JSON must not contain comments or trailing commas. JavaScript number precision limits apply.

Frequently asked questions

Format and validate JSON — What should I check before using this tool?

JSON must not contain comments or trailing commas. JavaScript number precision limits apply.

Which files can I choose?

Choose files in JSON format. Maximum files per batch: 1.

How can I adjust the result?

Indentation.

Understand the formats

JSON

JSON represents objects, arrays, strings, numbers, booleans and null. Property names use double quotes; comments are not part of standard JSON.

Format JSON for inspection, flatten suitable records into a CSV table, or combine JSONL records into a JSON array.

JavaScript cannot represent every large integer exactly. CSV has no universal type system, so a JSON-to-CSV round trip can change types or nested structure. Keep the source data.

When is this useful?

Indent one-line JSON for reading and structural checks. Invalid syntax must be corrected before formatting.

Input and result example

compact JSON → indented valid JSON

Examples illustrate the workflow; actual size, support and recognition depend on the source and settings.

Related guides

Check CSV and Excel data before importFile conversion and error basics