Data Tools
Free online data tools for developers. Validate YAML, format JSONL for AI training, create Markdown tables, and build JSON schemas. All processing happens in your browser - your data never leaves your device.
Markdown Table
Create markdown tables with a visual editor
YAML Validator
Validate YAML and convert between YAML and JSON
JSONL Formatter
Convert data to JSONL for AI fine-tuning
JSON Schema Builder
Build JSON schemas for OpenAI structured outputs
ASCII Table
Interactive ASCII character reference with decimal, hex, binary, and octal values
Why Use Our Data Tools?
Working with structured data is essential for modern development. Our free data tools help you validate configuration files, prepare training data for AI models, create documentation tables, and define data schemas.
100% Private: Unlike other online tools, your data never leaves your browser. All processing happens locally using JavaScript, so you can safely work with sensitive configuration and training data.
No Limits: Process as much data as you want, as often as you need. No sign-ups, no usage caps, no premium tiers.