BYTETOOLS

YAML Formatter

Format and re-indent YAML online. Normalise indentation, collapse blank lines, sort keys and rewrite flow collections as block style, privately.

Drop a .yml or .yaml file here or click to browse

What is the YAML Formatter?

The ByteTools YAML Formatter tidies messy YAML by parsing it and printing it again from scratch. Ragged indentation is normalised to the width you choose, runs of blank lines collapse, flow collections like {a: 1} are rewritten as block style, and sequence dashes line up neatly under the key that owns them.

  • Re-indents the whole document to 2, 4 or 6 spaces
  • Rewrites flow collections as block style (or the reverse)
  • Keeps each # comment attached to the key below it
  • Optional alphabetical sorting of mapping keys
  • Reports lines in, lines out and character count
  • Everything runs locally — nothing is uploaded

How to use the YAML Formatter

  1. 1

    Paste your YAML into the input box, or drop a .yml or .yaml file onto the drop zone.

  2. 2

    Choose an indent width of 2, 4 or 6 spaces.

  3. 3

    Tick 'Sort mapping keys A–Z', 'Compact flow style' or untick 'Keep # comments' as needed.

  4. 4

    Click Format YAML, then Copy the tidied document or Download it as a .yaml file.

About the YAML Formatter

The ByteTools YAML Formatter tidies messy YAML by parsing it and printing it again from scratch. Ragged indentation is normalised to the width you choose, runs of blank lines collapse, flow collections like {a: 1} are rewritten as block style, and sequence dashes line up neatly under the key that owns them.

Comments are not thrown away. Each # comment line stays attached to the key or sequence item that follows it, so the notes your team left in a CI pipeline or Helm values file survive the reformat. You can also switch comments off if you want a stripped, minimal file.

Formatting runs 100% locally in your browser. Your YAML is never uploaded or stored, so pipelines, manifests and configuration containing internal hostnames or service names stay entirely on your own machine.

Frequently asked questions

How do I fix the indentation in a YAML file?

Paste the file, pick your indent width and click Format YAML. The document is re-parsed and printed again with consistent indentation, so mixed 2-space and 4-space blocks all end up the same.

Will formatting delete my comments?

No, as long as 'Keep # comments' stays ticked. Comment lines are re-attached above the key or sequence item they preceded in the original file. Comments written at the end of a value line are the one exception and are dropped.

Why did my quoted numbers stay quoted?

Because removing the quotes would change the type. A value like "01234" or "true" is a string in the original document, so the formatter keeps the quotes to preserve exactly what the file means.

Does the formatter change my data?

It changes layout, not content. The document is parsed to a value tree and printed again, so the resulting YAML parses to the same data — but purely cosmetic details like the original quoting style are normalised.

Can it sort keys alphabetically?

Yes. Tick 'Sort mapping keys A–Z' and every mapping is emitted in alphabetical order. That makes two versions of the same configuration file far easier to diff line by line.

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