YAML formatter

Format YAML, keep comments, and see a JSON conversion.

Privacy: runs in your browser

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English

Your text

Indentation

Your result

Save a draft on this device

Save edits to this draft

Draft saving is off. Nothing is uploaded.

Indentation is part of YAML

The YAML parser reports the line and column of invalid input. Formatting keeps comments. Convert to JSON reads the values, so comments and YAML-specific presentation are not part of that output.

Next: JSON formatter

Worked example

octopus: arms: 8 is a mapping inside another mapping. Replacing indentation with tabs can make it invalid.

Before you rely on the result

One document at a time is supported. Custom tags are not interpreted, and unsafe integers are rejected for JSON conversion rather than rounded. Cyclic aliases cannot become ordinary JSON.

Help with the result

How to repair JSON without losing values

Cite this page

Citation style

ToolOctopus. “YAML formatter.” Updated 2026-10-11. https://tooloctopus.com/yaml-formatter.

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