About Us
DiagonalCalculator.com was built for one simple moment we’ve all had: you’re sketching a layout, checking a screen size, sizing a frame, or validating a design—and you just need the diagonal (and the related geometry) immediately.
Instead of juggling formulas, unit conversions, and multiple tabs, we created a clean tool where you can pick what you already know (two sides, side + area, side + perimeter, or side + angle) and see the diagonal update in real time—along with area, perimeter, circumcircle radius, and angle outputs.
What makes this tool different
- Multiple “Given” modes. Solve the diagonal from sides, area, perimeter, or angles—without switching calculators.
- Unit-aware results. Convert common units and keep linear vs. squared units consistent for area.
- Real-time output. No “Calculate” button—results refresh as you type so you can iterate quickly.
- Visual intuition. The diagram responds to your inputs, helping you understand what the numbers mean.
- Formula clarity. We include math explanations (rendered with clean equation formatting) so it’s not a black box.
- Privacy-first. The calculator is designed to work in your browser without accounts.
Who it’s for
Students verifying homework, engineers double-checking dimensions, designers working with layouts, DIY builders planning cuts—anyone who would rather think about their project than re-derive formulas.
Our promise
- Clarity. A calm interface that makes inputs and outputs obvious.
- Speed. Lightweight pages that load fast and respond instantly.
- Accuracy. Careful math and sensible rounding—plus transparency about assumptions.
- Respect. No forced accounts; minimal data collection.
Say hello
Have feedback, found an edge case, or want a new geometry mode? We’d love to hear it. The best way to reach us is the contact page.
Last updated: November 28, 2025