YAML Formatter

Format, validate, and align YAML configuration files.

Local ProcessingLocal processing: your data never leaves this device

Input YAMLEditable

Output YAMLRead-only

Why use an expert validator for YAML?

YAML's positional indentation easily causes errors in CI/CD. Our system continuously corrects and aligns any document before deploying it to Kubernetes.

Debugging without exposing DevOps secrets

It is highly harmful to paste files with embedded passwords into third-party internet validators. We mitigate this by validating entirely with your local browser.

What this tool does

YAML failures are often caused by tiny indentation mistakes that are hard to see in copied snippets. This page helps you validate and clean YAML quickly before it lands in CI, infrastructure or application config.

Formats YAML content into consistently indented, readable output that is easier to review and edit.
Validates YAML syntax and flags common issues such as inconsistent indentation, tab characters and invalid key structures.
Helps developers clean up YAML copied from tickets, chat messages or documentation before using it in CI, infrastructure or application config.

How to use it

1
Paste the YAML content into the input editor.
2
Use Format to get clean, readable output you can review, commit or share.
3
Use Validate to confirm the YAML is syntactically correct before adding it to a pipeline or manifest.
4
Copy the formatted output into your repository, config file or infrastructure definition.

Example

A developer pastes a Kubernetes manifest snippet copied from a documentation page and discovers mixed indentation that would cause the deployment to fail.

apiVersion: apps/v1
kind: Deployment
metadata:
  name: my-app
spec:
 replicas: 2

Validation error: inconsistent indentation at spec.replicas. Expected 2 spaces, found 1.

Use cases

Checking Kubernetes, Docker or CI configuration snippets.
Cleaning up YAML copied from chat, docs or tickets before committing it.
Validating manifest changes before deployment or code review.

Common mistakes

Using tabs instead of spaces

YAML does not allow tab characters for indentation. They cause parse errors that are easy to miss when the content looks correct visually.

Inconsistent nesting depth

YAML is sensitive to the exact number of spaces used for each nesting level. Even one extra or missing space can change how the document is parsed.

Copying YAML from rendered documentation

Documentation pages sometimes render YAML with different whitespace than the raw source. Always validate after copying from a browser.

FAQ

Why does YAML fail even when it looks correct?

YAML is whitespace-sensitive. Tabs, inconsistent indentation depths and mixed space widths can all cause invisible parse errors.

Can I validate Kubernetes or CI manifests here?

Yes. This tool checks YAML syntax. For deeper schema validation of Kubernetes resources, you also need tool-specific validators.

Does this upload my YAML data?

No. YAML content is processed locally in the browser.

What is the difference between YAML 1.1 and 1.2?

YAML 1.2 is stricter and more predictable. The most notable change is that booleans like yes, no, on and off are no longer automatically converted in YAML 1.2.

Can I use this for Docker Compose files?

Yes. Docker Compose files are YAML and can be validated and formatted here.

Privacy and security

YAML content is processed locally in the browser.
No manifest or config file is uploaded for validation.
That is useful when you are working with private infrastructure or deployment settings.

Related tools

Related tools for the next step in the same workflow:

XML Formatter & Validator JSON Formatter & Validator Diff Checker

Next step

Validate the YAML locally, then compare revisions or convert formats if your config workflow continues.