Slope calculator — % ↔ degrees ↔ 1:N

Enter a slope in any form to get it as a percentage, in degrees and as a 1:N ratio — for ramps, roofs and roads.

%
Degrees
m
m
m
Shows the run and ramp length you need

Fill in the form — the result appears here instantly

How it works: Slope calculator

A slope can be written three ways: percent (rise ÷ run × 100), degrees (angle from horizontal) and 1:N (N units of run per unit of rise). A wheelchair ramp of 1:12 is about 8.33% or 4.76°.

Enter rise and run to work out the slope of something real and how long a ramp needs to be.

FAQ

What angle is a 100% slope?

45 degrees — the rise equals the run.

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