Enter two sidelengths and get the diagonal instantly.
Calculate diagonal measurements to verify perfect 90° corners
How to use this calculator
- Measure the two sides of your right angle (short and long run).
- Enter each value in meters, feet, or inches—the units just need to match.
- Review the diagonal value; if it matches your tape measurement, the corner is square.
- Tap Clear to reset and repeat down the line of your slab or framing.
Tip: On mobile, rotate your device or collapse the keyboard after entering each side to keep the diagonal result fully visible.
📏 Pythagorean precision in seconds
📱 Built for job-site mobile use
🌐 Works offline after first load