Compare YAML Online
Paste two YAML configs below and see differences highlighted.
About YAML Compare Online
Compare two YAML files side by side. Find differences in configuration, keys, and values. Free YAML diff tool. All processing happens in your browser — nothing is uploaded to any server. Completely free, no sign-up required.
YAML (YAML Ain't Markup Language) has become the standard configuration format for modern DevOps workflows, cloud infrastructure, and application deployment. Our YAML comparison tool is indispensable for DevOps engineers, cloud architects, SREs, and backend developers who work with Kubernetes manifests, Docker Compose files, Ansible playbooks, GitHub Actions workflows, CI/CD pipelines, Helm charts, and application configuration files. Use it to review changes before deploying to production, compare configurations across environments (development, staging, production), audit drift in infrastructure-as-code files, and validate that automated tools have not introduced unintended modifications.
YAML's whitespace-sensitive syntax makes it particularly prone to subtle bugs — a single indentation change can move a key from one scope to another, completely altering the meaning of your configuration. Our diff tool highlights every line-level change including modified values, added or removed keys, changed indentation levels, altered list items, and updated multi-line strings. It is especially valuable for comparing Kubernetes deployment manifests (detecting changed resource limits, updated image tags, modified environment variables), reviewing Terraform variable files, auditing changes to CloudFormation templates, and comparing Helm chart values across releases.
Best practices for comparing YAML files: always use consistent indentation (2 spaces is the convention), keep keys in a predictable order, and avoid mixing flow style (inline) with block style for the same data. If you are comparing YAML files that use anchors (&) and aliases (*), the tool compares the raw text including anchor definitions rather than resolved values. For multi-document YAML files (separated by ---), the tool will compare them as a single text block. All processing runs locally in your browser, making it safe for comparing YAML containing cloud credentials, deployment secrets, database connection strings, and proprietary infrastructure configurations.
Frequently Asked Questions
How does YAML indentation affect the comparison results?
YAML is indentation-sensitive — indentation defines the structure and hierarchy of your data. Our tool compares text exactly as provided, so any change in indentation will be highlighted as a difference. This is actually a feature, not a limitation, because in YAML a change in indentation can fundamentally alter the meaning of your configuration (moving a key to a different scope). The tool helps you catch these potentially breaking indentation changes that might otherwise go unnoticed.
Can this tool compare YAML files with anchors and aliases?
Yes. The tool compares the raw YAML text, including anchor definitions (&anchor_name) and alias references (*anchor_name). It does not resolve or expand anchors before comparing, which means you will see differences in anchor definitions themselves. This is useful for verifying that shared configuration blocks (defined via anchors) have not been inadvertently modified. If you want to compare the resolved/expanded YAML, expand anchors in both documents before pasting.
What types of YAML configuration files can I compare?
You can compare any YAML content including Kubernetes manifests (deployments, services, configmaps), Docker Compose files, Ansible playbooks and roles, GitHub Actions/GitLab CI workflows, Helm chart values, Spring Boot application.yml files, Terraform variables, AWS CloudFormation templates, Swagger/OpenAPI specifications, and any other YAML-formatted configuration. The tool handles all valid YAML syntax including sequences, mappings, multi-line strings, and complex nested structures.
Can I compare .yml and .yaml files — is there a difference?
The .yml and .yaml extensions are completely interchangeable — they both contain YAML-formatted content and are parsed identically. You can compare content from either file type in this tool. Simply paste the contents regardless of the original file extension. The comparison works on the text content itself, not the file extension, so there is no distinction between .yml and .yaml in terms of how the diff is performed.
Is it safe to compare YAML files containing secrets or credentials?
Yes, completely safe. All comparison processing happens locally in your web browser. No YAML content is ever transmitted to any server, stored remotely, or accessible to third parties. This makes the tool appropriate for comparing configuration files containing database passwords, API keys, cloud credentials, TLS certificates, and other sensitive values. Your infrastructure secrets remain entirely on your machine throughout the comparison process.