Stairs

Stair Angle Calculator

Your measurements : vertical rise, horizontal run. Your estimate : angle, slope, rise per 12 run.

Your measurements

How the calculation works

Stair Angle Calculator

Angle = atan(Vertical rise / Horizontal run) × 180 / π; Slope = 100 × Vertical rise / Horizontal run

Before you order

  • A straight flight is assumed. The upper floor is the final landing, so there is one fewer tread than riser. No headroom, landing, handrail or local code validation is included.
  • Planning estimate only. This is not a structural design, a safety approval or a local code check.

Worked example

Vertical rise
2 m
Horizontal run
4 m

Angle 26.57 °

Slope 50 %

Keep planning

My project

Optional local saving. Your measurements stay in this browser for 30 days. Clear them at any time.

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