Construction Calculators
Stair Calculator
Standard vs flush mount; derive run, rise, step count, and total run from what you know—plus stringer length, angle, and comfort/code hints like Omni’s stair tool.
Pick whether you know tread run or total horizontal run, and riser height or step count; enter total rise and mount type to compute the rest (same relationships as Omni Calculator’s stair formulas).
Stringer uses the right triangle: length √(total run² + stringer height²), angle from arcsin(height/length). Comfort band 2×rise + run ≈ 60–65 cm; IRC-style warnings are illustrative—verify local code.
Choose what you already know (run vs total run; rise vs step count), set mount and total rise—the rest follows the same relationships as Omni’s stair calculator.
I know…
and…
Mount
Total rise
cm
Run of one step
cm
Rise of one step
cm
Your stairs
Run of one step
cm
Total rise
cm
Rise of one step
cm
Number of steps
Total run
cm
Rise of the bottom step
cm
Stringer height
cm
Stringer length
cm
Angle
°