Ramp Calculator 2026
Instantly calculate ramp length, slope angle, gradient, and ADA compliance for wheelchair ramps, loading docks, and DIY construction projects.
Ramp Dimensions & Parameters
Enter known values — the calculator resolves all remaining measurements
Height difference from bottom to top of ramp
Horizontal distance covered by the ramp
Clear width between edges / handrails (ADA minimum: 914mm / 36 in)
Determines compliance thresholds shown in results
Flat platform at top/bottom (ADA minimum: 1524mm / 60 in)
Ramp Calculations
Slope, length, gradient & compliance status
Enter your ramp rise and run above, then click Calculate Ramp Dimensions to see slope angle, gradient, ramp length, and ADA compliance.
Ramp Gradient Standards
Standard slope ratios and their angle equivalents for common ramp applications. Always verify with local building regulations before construction.
| Use Case | Max Gradient | Slope Ratio | Angle (°) | Notes |
|---|---|---|---|---|
| ADA Wheelchair Ramp | 8.33% | 1:12 | 4.76° | USA federal standard |
| UK Part M Wheelchair Ramp | 12.5% | 1:8 | 7.13° | Short ramps ≤2m only |
| Pedestrian Pathway | 5% | 1:20 | 2.86° | Comfortable walking grade |
| Loading Dock (Manual) | 10% | 1:10 | 5.71° | Hand trucks & pallet jacks |
| Loading Dock (Forklift) | 15% | 1:6.7 | 8.53° | Max recommended for forklifts |
| Residential Driveway | 20% | 1:5 | 11.31° | Practical max for standard cars |
| Car Park Ramp | 15–17% | 1:6 | 8.5–9.5° | BS 6399 / local authority |
Ramp Building FAQ
Answers to the most common questions about slope ratios, ADA compliance, ramp width, and gradient calculations for DIY and professional projects.
The Americans with Disabilities Act (ADA) requires a maximum slope ratio of 1:12 for wheelchair ramps — meaning for every 1 inch of rise, there must be at least 12 inches of run. This equals an 8.33% gradient or approximately 4.76 degrees. Cross slopes must not exceed 2% (1:50).
To calculate ramp length, use the Pythagorean theorem: ramp length = √(rise² + run²). Alternatively, if you know your desired slope ratio (e.g. 1:12), multiply the rise by 12 to get the minimum horizontal run, then calculate the hypotenuse. Our calculator does all of this automatically.
Slope angle is expressed in degrees (e.g. 5°), calculated using arctangent of rise divided by run. Gradient (or slope ratio) is expressed as a percentage or ratio (e.g. 1:12 or 8.33%), calculated as rise divided by run multiplied by 100. Both describe steepness — angles suit engineering drawings while gradients suit accessibility standards.
Commercial loading dock ramps typically range from 7% to 15% gradient (approximately 4° to 8.5°). Steeper slopes are acceptable for short distances or vehicles with high ground clearance, but anything above 15% can be dangerous for forklifts and hand trucks. Always consult manufacturer specifications for equipment used on the ramp.
ADA guidelines require a minimum clear width of 36 inches (914mm) between handrails for a wheelchair ramp. For two-way traffic or comfort, a width of 48 to 60 inches (1220–1524mm) is recommended. UK Part M guidance similarly requires 1500mm for shared pedestrian use. Always check local building codes for your specific requirements.
Yes. ADA standards require a flat landing of at least 60 inches (1524mm) in length at both the top and bottom of every ramp run, and wherever a ramp changes direction. Landings must be at least as wide as the ramp itself. For longer ramps exceeding 30 feet (9m) of rise, intermediate landings every 30 inches (762mm) of rise are also required.