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GigAI Tools

YAML Formatter & Converter, Beautify, Lint, YAML ↔ JSON Online

Paste messy YAML and get it re-indented, key-sorted and validated instantly, or convert it to JSON and back. When it won't parse we point at the exact line and column. 100% client-side, nothing uploaded.

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What is the yaml formatter?

The YAML Formatter re-indents, cleans and validates YAML, or converts YAML to JSON and back, with key sorting and flow or block style. When input won't parse, it reports the exact error line and column. Free and 100% client-side, your YAML stays in the browser with nothing uploaded.

The GigAI YAML Formatter is a desktop-grade YAML editor that runs entirely in your browser. Paste, drop or type YAML and it normalises the indentation to 2, 4 or 8 spaces, sorts every mapping key alphabetically for clean diffs, and can re-emit your document in compact flow style (`{a: 1, b: 2}`) or readable block style. It doubles as a two-way converter: turn a Kubernetes manifest or GitHub Actions workflow into JSON to feed a tool that only speaks JSON, then convert the JSON back to clean YAML. What sets it apart from the usual online converters is the error experience. When your YAML is invalid we surface the precise line and column, quote what the parser expected, and give you a one-click jump straight to the offending character, so a mis-indented key or a stray tab stops being a five-minute hunt. It keeps a full undo/redo history, works from the keyboard, and shows document stats at a glance. Because parsing and dumping happen locally with js-yaml, your manifests, secrets, CI configuration and infrastructure files are never uploaded, logged or seen by anyone. Close the tab and it's gone.

Difficulty:
Easy
Typical time:
~15s
Processing:
100% browser processing

Last updated

How to use the yaml formatter

  1. 1

    Paste, drop or import YAML

    Paste into the left editor, drag a .yml/.yaml file onto it, or click to browse. Or load a built-in sample to try it instantly.

  2. 2

    Pick a mode & options

    Choose Format, YAML → JSON or JSON → YAML, then set the indent, whether to sort keys, and flow vs block style. Everything re-runs live.

  3. 3

    Fix any errors

    If the input is invalid, read the exact line and column in the error banner and click Jump to error to place your cursor on it.

  4. 4

    Copy, download or share

    Copy the result, download it as a .yaml or .json file, or share a link that reopens the tool with your input pre-loaded.

What YAML Formatter includes

  • Re-indent & beautify

    Normalise inconsistent indentation to 2, 4 or 8 spaces, strip trailing noise and emit clean, canonical YAML: the fix for manifests copied out of a chat window.

  • YAML ↔ JSON both ways

    Convert YAML to pretty JSON to feed a JSON-only tool, or turn JSON back into readable block YAML. Switch direction with one control and everything re-runs live.

  • Exact error line & column

    When YAML won't parse we show the precise line and column, quote what the parser expected, and offer a one-click jump to the character. No counting spaces by hand.

  • Sort keys for clean diffs

    Alphabetise every mapping key recursively so two versions of a config compare cleanly in Git and review focuses on real changes, not reshuffled fields.

  • Flow or block style

    Re-emit collapsed flow style like `{name: web, port: 80}` for compact snippets, or expand to readable multi-line block style: your choice, applied instantly.

  • 100% in your browser

    Parsing and dumping run locally with js-yaml on your device. No manifest, secret, token or CI file is ever uploaded, stored or logged.

Why use our yaml formatter

Fix broken indentation in seconds

YAML lives and dies by whitespace. Re-indenting normalises tabs and ragged spacing into a valid, canonical document instead of a manual space-counting exercise.

Bridge YAML and JSON toolchains

Convert a Helm values file or Actions workflow to JSON for a linter or API that only speaks JSON, then convert the result straight back to clean YAML.

Clean diffs with sorted keys

Sorting mapping keys produces a canonical form, so pull-request diffs on configuration stay small, meaningful and easy to review.

Private by design

Because it runs locally, you can safely format YAML containing secrets, API keys or internal infrastructure: none of it leaves your machine.

Built for the way you work

From quick one-off fixes to daily workflows, see how people put this tool to use.

  • DevOps / Platform engineer

    Clean up a Kubernetes manifest

    Re-indent a manifest pasted from Slack, sort keys so the deployment diffs cleanly, or convert it to JSON to feed a policy checker that only reads JSON.

  • Backend developer

    Fix a CI workflow that won't parse

    When a GitHub Actions or GitLab CI file throws on load, jump straight to the line the parser rejects, usually a tab, a bad indent or an unquoted colon.

  • Frontend developer

    Convert config between formats

    Turn a JSON config into readable YAML for a tool that prefers it, or flatten a YAML fixture to JSON to paste into a test, round-trip either direction.

  • Technical writer

    Tidy YAML for docs

    Beautify example snippets to a consistent indent and style so code blocks in documentation are correct, readable and copy-paste-safe.

Supported formats

Accepts YAML, YML, JSON and TXT, and produces YAML and JSON, all processed locally in your browser.

Input formats
  • YAML
  • YML
  • JSON
  • TXT
Output formats
  • YAML
  • JSON

Frequently asked questions

Common problems, solved

Hit a snag? Here are quick fixes for the issues people run into most.

  • It rejects my file with 'bad indentation' or a tab error.

    YAML forbids tab characters for indentation. Click Jump to error, then replace tabs with spaces on the reported line. Re-formatting afterwards normalises the whole document to a consistent space indent.

  • A value like `on: true` or `version: 3.10` changed meaning.

    YAML auto-types bare scalars, so `on`, `yes`, `no`, `off` become booleans and `3.10` becomes the number 3.1. Quote the value ('3.10', "on") to keep it an exact string on the round-trip.

  • Only the first document came through.

    This tool reads a single YAML document. If your file uses `---` separators for a multi-document stream, format each document separately or remove the extra separators first.

  • Anchors and aliases disappeared after formatting.

    The formatter resolves `&anchor`/`*alias` references and emits the expanded value so the output is self-contained. If you need the references preserved verbatim, format a copy and keep the original.

Get the most out of it

  • Use Sort keys before committing generated YAML so future diffs stay small and reviewable.

  • Press Ctrl/Cmd+Enter to re-run instantly, and Ctrl/Cmd+S to download the result.

  • Getting a parse error you can't see? It's almost always a tab character or a key indented by an odd number of spaces.

  • Quote values like '3.10', 'on' and 'yes' when you need them to stay strings, not numbers or booleans.

  • Convert to JSON and back to YAML to instantly canonicalise a hand-edited file into a consistent style.

What's new

Recent updates and improvements to the yaml formatter.

  1. Initial release, live YAML formatting with 2/4/8-space indent, key sorting, flow/block style, YAML ↔ JSON conversion, precise line + column errors with jump-to-error, drag-drop import, undo/redo and shareable links.

  2. Added keyboard shortcuts (run, download, clear, undo/redo) with an in-tool shortcuts helper and a curated set of sample documents (Kubernetes, GitHub Actions, docker-compose).

  3. Refined error messages for tab-indentation and unquoted-colon mistakes, and added document stats (keys, lines, output size).

Your privacy is built in

Your YAML is parsed and dumped entirely in your browser with js-yaml. It is never uploaded to any server. Nothing is stored, logged or transmitted, so you can safely format manifests, CI configuration or files containing secrets. Close the tab and every trace is gone.

  • Runs in your browser
  • No uploads
  • Nothing stored

Ready to try the yaml formatter?

Free, private and instant. YAML Formatter runs right in your browser.