Accurate mm & inch ruler app with fast calibration, unit converter, and smart on-screen measuring tools

Ruler Cm is a precise and easy-to-use measurement toolkit that turns your smartphone or tablet into a reliable mm ruler, inch ruler, vernier caliper, and online ruler. Perfect for everyday tasks, DIY projects, and digital measurement needs, it offers smooth calibration, intuitive controls, and support for multiple units.

Designed for accuracy and convenience, this digital measuring tool helps you determine length, thread pitch, straight lines, and more—ideal for users searching for “best measurement app for Android,” “digital ruler for crafts,” or “screen ruler for designers.” With support for over 20 languages, it’s a practical companion for anyone needing quick mobile measurements.

Key Features

• Length measurement, thread pitch determination, straight line mode, and length calculation
• Smart unit converter: inches to millimeters, inches to centimeters, and more
• Fast calibration, vertical/horizontal ruler modes, and measurement by any device side
• Integrated vernier caliper and online ruler for high-precision tasks
• Beautiful, functional, multilingual design optimized for smartphones and tablets