Belt Length Quick

Dev Jang

About this app

Belt Length Quick is a simple pulley belt reference calculator for Android.

Enter the driver pulley diameter, driven pulley diameter, center distance, and driver RPM to estimate belt length, driven RPM, speed ratio, belt speed, and wrap angle. Switch between open and crossed belt arrangements, copy the result, and save common calculations on your device.

Useful for quick workshop, study, and DIY planning checks.

Features:
- Open belt and crossed belt calculations
- Belt length in millimeters and inches
- Driven RPM and speed ratio
- Belt speed and wrap angle reference
- Copy result summary
- Save local calculation history
- Formula notes inside the app

This app is a planning reference only. Always confirm belt section, pitch line, tension, wrap, load, manufacturer data, and safety requirements before purchase, installation, or operation.

What’s new

Added nearest stock-length checks for 10 mm and 0.5 inch belt sizes.