Runs fully in your browser. Inputs stay on your device. See recent fixes on changelog.
YAML Validator
Validate YAML syntax and check for errors.
FreeRuns in browseryaml validatorvalidate yaml
Cmd/Ctrl+Enter Primary actionCmd/Ctrl+Shift+L Load sampleCmd/Ctrl+Shift+X Clear/resetCmd/Ctrl+Shift+C Copy result
About YAML Validator
Validate YAML syntax and check for errors online for free. Detect tab characters, indentation issues, and structural problems in your YAML config files. Applies consistent indentation and style rules across your entire document with one click. Validation mode checks syntax correctness and reports detailed, actionable error descriptions. Everything runs client-side in your browser for maximum speed and privacy — no data is sent to any server, and no signup is required.
Related tools: JSON Formatter & Validator, XML Formatter & Validator, TOML Validator
How to Use YAML Validator
- Paste your code or data into the editor.
- Click Format to beautify or Validate to check for errors.
- Copy the cleaned output or review any issues found.
Frequently Asked Questions
What is YAML Validator?
Validate YAML syntax and check for errors online for free. Detect tab characters, indentation issues, and structural problems in your YAML config files.
What validation rules are applied?
Validation checks for correct syntax according to the language or data format specification. This includes balanced brackets, proper quoting, valid escape sequences, and structural integrity of the document.
Does formatting change the data?
No, formatting only affects whitespace, indentation, and line breaks. The actual data content and semantics remain identical, ensuring your code or configuration behaves exactly the same after formatting.
What indentation options are available?
You can choose between spaces and tabs, and configure the number of spaces per indent level (commonly 2 or 4). The formatter applies your chosen style consistently throughout the entire document.
Is YAML Validator free to use?
Yes, formatting and validation are completely free. There are no usage caps, and no signup or account is ever required.
Is my data safe when using YAML Validator?
Yes, your code and data stay on your device. All formatting and validation happens locally in the browser with no server communication.