thaitools.techPractical tools for life in Thailand
English interface

JSON formatter and syntax validator

Format or minify JSON locally while preserving original numeric tokens.

ReviewedLow-impact
Saves this tool's name on this device only (up to 20). No form values.
Only visible result text is included. Form fields are not read. Review sensitive values before sharing.

Up to 200,000 characters and 100 nesting levels. No comments or trailing commas. Data stays on this device.

Enter values, then process to see the result.

How to use it

  1. Paste JSON and select pretty print or minify.
  2. Process the text to validate its syntax.
  3. Copy the result after reviewing it.

Important limitation

Up to 200,000 UTF-16 code units and 100 nesting levels. Comments, JSON5 and schema validation are not supported. Duplicate keys remain unchanged.

The interactive form is fully localized in English.

Reviewed 2026-09-09; next review 2027-09-09.

Core calculations, cited sources and main test cases have been reviewed within the stated scope.

Sources

RFC 8259 — JSONIETF / RFC Editor · opens in a new tabSupports the method and scope stated on the tool page; consult the source for case-specific rules.Source checked 2026-09-09
Traceable review record

Review history

Site changelog

This is the recorded review history available in the repository, not an inferred release history. Dates are added only when evidence is recorded.

  1. Current review snapshot recorded

    Core calculations, cited sources and main test cases have been reviewed within the stated scope.

    Method version: review-2026-09-09

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