Use a coin or a credit card to calibrate the ruler anywhere when you don't have a real ruler with you!

- Ad free for real forever!
- Pick your units: fractional inches decimal inches centimeters or millimeters
- Calibrate your ruler with a credit card to get you started anytime anywhere
- Don't have a credit card with you? Calibrate your ruler with a coin!
- Calibrate your ruler with a real ruler to achieve the best precision in your measurement transfers
- Manually set the ruler to a known length for accurate measurements
- Night mode to save battery (on AMOLED screens) and to relieve your eyes at night
- Save your measurements for future use
- No permissions required