Developer Tools

Log Prettifier

Paste raw JSON log output and get human-readable, formatted log entries in seconds. Extracts level, timestamp, message, and structured data, transforming walls of minified JSON into readable logs.

Runs in your browser No data sent to servers Copy or download result
json Raw log output
Runs in your browser; code never leaves your device

Features

  • Formats JSON log lines with indentation
  • Highlights log level (ERROR, WARN, INFO, DEBUG)
  • Extracts timestamp and message prominently
  • Handles concatenated JSON log streams
  • Copy or download formatted output

How to use it

  1. Paste your raw log output.
  2. Formatted log entries appear instantly.
  3. Copy the output for sharing or analysis.

Use cases

  • Debugging production logs from cloud functions
  • Reading structured logs from Node.js, Python, or Go services
  • Sharing readable logs in incident reports

Limitations

  • JSON lines are pretty-printed and plain logs are kept readable.
  • Very large input can be slower on older devices.
  • This utility is designed for common snippets and local inspection, not as a full security or language-specific validator.
See also

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Questions & answers

Frequently asked

Does it work with multi-line logs?

Yes. The tool handles both single-line JSON objects and newline-delimited JSON (NDJSON) streams.