YAML Formatter
Format, validate YAML data and convert to JSON with syntax highlighting and multiple format options
YAML Validation Error
About YAML Formatter
YAML (YAML Ain't Markup Language) is a human-readable data serialization format commonly used for configuration files in DevOps, cloud infrastructure, and application development.
This YAML Formatter tool helps you format, beautify, minify, and validate your YAML documents. It also supports converting YAML to JSON format with syntax highlighting.
Key Features
How This Tool Processes YAML
Indentation Standardization
Applies consistent 2-space indentation to all nested levels. YAML requires spaces (not tabs) for indentation. Example: Lists and mappings are properly aligned to reflect hierarchy visually.
Line Break Optimization
Ensures each key-value pair and list item appears on its own line. Long strings may be folded or literal blocks (| or >) for readability. Removes trailing whitespace that could cause parsing errors.
Comment Preservation
Maintains # comments with proper indentation. Comments are aligned with their associated elements. Critical for documentation in configuration files like docker-compose.yml or Kubernetes manifests.
Quote Normalization
Standardizes string quoting (single vs double quotes). Automatically quotes strings containing special characters (:, -, ?, etc.). Preserves existing quotes when necessary for value integrity.
File Size Impact
YAML formatting typically increases file size by 15-30% due to added indentation and spacing. Unlike JSON/XML, YAML has no minification mode - whitespace is structurally significant. Server-side Gzip compression achieves 60-80% size reduction.
| Scenario | Original | Formatted | Gzipped |
|---|---|---|---|
| Configuration file (docker-compose) | 15 KB (compact) | 18-20 KB (+20-30%) | ~3-4 KB (75-80% total) |
| Data export with comments | 40 KB (formatted) | 40 KB (same) | ~8-10 KB (75-80% total) |
| Kubernetes manifest (complex) | 25 KB (compact) | 30-32 KB (+20-30%) | ~5-7 KB (75-80% total) |
How to Use YAML Formatter
- Paste your YAML code into the input editor or drag and drop a file.
- Adjust formatting options like Indent Size (2 or 4 spaces) and Quote Strings.
- Click 'Format' to beautify, 'Validate' to check for errors, or 'To JSON' to convert.
Why Use Our YAML Tool?
Instant Validation: Detects syntax errors, especially the common 'Tab vs Space' issue.
DevOps Ready: Perfect for formatting Docker Compose, Kubernetes manifests, and CI/CD configs.
Bidirectional Conversion: Seamlessly convert between YAML and JSON.
Client-Side Processing: Your data never leaves your browser (100% Secure).
Advanced Features: Supports minification and sorting keys for cleaner diffs.
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