YAML Validator & Linter (DevOps Config Checker)
YAML is the backbone of modern cloud infrastructure, but its strict indentation rules and case-sensitivity make it notoriously difficult to debug manually. Whether you are building complex Kubernetes deployments, Docker Compose stacks, or GitHub Action workflows, a single missing space can break your entire production pipeline. This tool provides an instant, browser-native linter that catches syntax errors and provides a clean JSON schema preview of your data.
100% Private & Secure
This tool runs completely inside your browser using client-side WebAssembly and JS. Zero data is ever sent to our servers.
YAML Input
Validation Status
Awaiting Input
How to use this tool
- Paste your YAML configuration snippet into the 'YAML Input' editor on the left.
- The validator automatically scans your code for syntax violations and indentation errors.
- If a structural error is found, the 'Linter Trace' will identify the exact line requiring correction.
- Once valid, review the 'Object Schema Preview' to ensure your data hierarchy is being parsed correctly by service engines.
- Copy your validated code directly back into your `deployment.yaml` or `docker-compose.yml` file.
Example Usage
services:
web:
image: nginx
ports:
- "80:80"Status: Valid YAML Syntax | Schema Preview displayed.
When to use this tool
- Debugging Kubernetes 'invalid manifest' errors during `kubectl apply` commands.
- Verifying complex Ansible Playbook logic before running migrations across server clusters.
- Identifying illegal 'Tab' characters in YAML files (which are strictly prohibited by the specification).
- Converting messy YAML configurations into clean JSON for API prototyping and data transformation.
Frequently Asked Questions
Why is YAML indentation so strict?
YAML uses white-space indentation to define its structure and hierarchy, similar to Python. This removes the need for braces `{}` and semi-colons, but it means that even a single extra space can change the meaning of your configuration or cause the parser to fail entirely.
Can I use tabs in YAML?
No. The YAML specification strictly forbids the use of the Tab character for indentation. You must always use spaces (typically 2 or 4). Our linter will automatically flag tab characters as syntax violations.
How do I define a list in YAML?
Lists are defined using a hyphen `-` followed by a space. Each list item must be at the same indentation level. Example: `ports: - 80 - 443`.
Is this safe for production secrets?
Yes. This tool is 100% client-side. Your configuration data (including potential environment variables or secrets) is processed entirely within your browser and never leaves your machine.
What is a 'YAML anchor'?
Anchors (&) and Aliases (*) allow you to avoid duplicating data in large YAML files by defining a property एकदा (once) and referencing it later. Our validator supports standard anchor and alias parsing.