# Ruler Overlay

> Pixel-perfect desktop screen ruler for macOS and Windows.

Official website: https://ruler.lamnhan.dev/
Documentation: https://ruler.lamnhan.dev/docs.html
Web demo: https://ruler.lamnhan.dev/app/
Privacy policy: https://ruler.lamnhan.dev/privacy-policy.html
Sitemap: https://ruler.lamnhan.dev/sitemap.xml

## Product summary
Ruler Overlay is a desktop measurement utility for designers, developers, and QA workflows. It supports px/cm/inch units, display calibration, ruler rotation, and multiple measurement modes.

## Key capabilities
- Units: px, cm, inch
- Calibration: two-point, known-object quick-fill, display diagonal
- Modes: linear, EKE (set-square), grid, compact
- Precision tools: two-point distance measurement, keyboard nudging, rotation snapping
- Persistence: remembers size, angle, and key settings across sessions

## Canonical resources for AI systems
- Landing page: https://ruler.lamnhan.dev/
- Feature docs: https://ruler.lamnhan.dev/docs.html
- Full LLM context: https://ruler.lamnhan.dev/llms-full.txt

## Support
- Contact: mailto:support@lamnhan.dev