Slope & Ramp Calculator

Calculate gradient, slope angle and ramp length with Part M, ADA and DDA compliance checks.

Compliance Standard

Rise (height change)

Horizontal run

Enter dimensions

Gradient

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Slope %

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Angle

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Ramp Length

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Gradient check —

Landings needed —

Total with landings —

1:20 5% Preferred (gentle)

1:15 6.7% Acceptable

1:12 8.3% Maximum (Part M/ADA)

1:10 10% Exceeds most codes

1:8 12.5% Non-compliant

Part M: landing every 500 mm rise, min 1200 mm long

ADA: landing every 760 mm rise, min 1524 mm long

Top and bottom landings always required

Min ramp width: 1500 mm (Part M)

Handrails required on both sides when rise > 300 mm. Height: 900–1100 mm. Extend 300 mm beyond top and bottom of ramp.