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Square Check (3-4-5 & Diagonal)
The diagonal for any rectangle so you can square a layout, plus a 3-4-5 check scaled to your size.
Enter both sides to see the diagonal.
Assumptions
- Measure both diagonals; when they match, the corners are 90°. If they differ, shift the far corner half the difference.
Planning numbers. Confirm quantities with your supplier, spec and local conditions before ordering.
Running a crew?HardHatOps — toolbox talks, time clock, sign-off records, daily duties. The field side.
Bidding and running jobs?IAOIntel — takeoffs, estimates, daily logs, spec intelligence. The office side.