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Logfmt ↔ JSON Converter

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What is Logfmt ↔ JSON Converter?

Logfmt Converter transforms between logfmt and JSON formats. Logfmt (log format) is a plain-text logging convention popularized by Heroku where each log line contains space-separated key=value pairs: `method=GET path=/api status=200 duration=45ms`. It's human-readable in the terminal but harder to query programmatically. Converting to JSON gives you structured data that's easy to filter, search, and analyze with log aggregation tools.

How it works

The parser splits each line on spaces while respecting quoted values (key="a b"). Boolean flags (words without =) are parsed as key=true. The encoder reverses this: JSON string values become key=value, numbers remain unquoted, and booleans become bare flags.

Features & Benefits

  • Converts logfmt key=value lines to structured JSON objects
  • Reverse: encode JSON objects back to logfmt format
  • Bulk processing - handles thousands of lines instantly
  • Runs entirely in your browser - log data never leaves your device

Frequently Asked Questions

What is logfmt?

Logfmt is a logging format popularised by Heroku and widely used in Go services. Each log line is a series of key=value pairs, making logs both human-readable and machine-parseable.

Are the values typed?

Logfmt is stringly typed - all values are strings. Bare words without = are treated as boolean true flags. Use JSON if you need typed values.

Is my log data sent anywhere?

No. All parsing and encoding happens in your browser using JavaScript. Nothing is uploaded.

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