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Developer Tools

Format Java Maps, convert Java Map output to JSON, and format and validate JSON in your browser without uploading your data.

  • Browser-based
  • No signup
  • Local processing

Developer tools

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3 tools

Java · Formatter

Java Map Pretty Formatter

Make nested Java Maps and Lists easier to read with consistent indentation.

Java · Converter

Java Map to JSON Converter

Turn Java Map-style text into formatted JSON with automatic scalar type conversion.

JSON · Formatter

JSON Formatter & Validator

Format, validate, or minify JSON in a few clicks. Find syntax errors as you work.

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Developer Guides

Practical guides for Java Maps, JSON, and common data-format problems.

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How to Pretty Print a Java Map

Compare Map.toString(), entry iteration, Jackson, Gson, and formatting existing Java Map output.

How to Convert a Java Map to JSON

Convert Java Maps with Jackson or Gson and handle Map.toString() output copied from logs.

Why Developer Tools

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