Ramp Slope Calculator
Calculate ramp slope, angle, required run, and total footprint from rise and run dimensions. Enter all lengths in the same unit.
Advanced ramp planning
For a custom target ratio, edit the target value in the page source or extend the selector for your project convention. Unit conversion is linear: inches, feet, millimetres, and metres may be used as long as inputs match.
Accessibility caution. Requirements vary by jurisdiction, occupancy, building type, handrails, landings, width, and surface. This planner is not code certification.
Ramp slope formula
Slope ratio denominator = run ÷ rise. Slope percentage = rise ÷ run × 100. Angle = atan(rise ÷ run). Required run = rise × target ratio denominator.
Worked example
A 24-unit rise over a 288-unit run is a 1:12 ratio, an 8.33% slope, and an angle of about 4.76°.
Assumptions
- Rise and run are positive straight-line dimensions in the same unit.
- Landings are added to the footprint but not the sloped run.
- Verify dimensions and local accessibility requirements with the authority having jurisdiction.