Slope Grade Calculator
Calculate slope grades, angles, and ratios with our easy-to-use calculator. This tool is essential for construction, landscaping, engineering projects, and more.
Nearly level (0%)
Ideal for most construction projects, sports fields
ADA Compliant
This slope meets ADA requirements for wheelchair ramps (max 8.33%)
Vehicle Access
This slope is suitable for most vehicles
Slope vs. Grade
Slope is typically expressed as a ratio of rise to run (y/x) in mathematics, while grade is usually expressed as a percentage in engineering and construction. Both describe the steepness of a line or surface.
Conversion Formulas
- Grade Percentage = (Rise ÷ Run) × 100
- Angle (degrees) = arctan(Rise ÷ Run)
- Grade Ratio = 1:(Run ÷ Rise)
- Slope (y/x) = Rise ÷ Run
Common Applications
- Civil engineering and road design
- Architecture and building construction
- Accessibility ramp design
- Drainage system planning
- Roof pitch calculations
- Hiking trail difficulty assessment
Standard Grades for Common Applications
- ADA-compliant ramps: 8.33% maximum (1:12 ratio)
- Residential driveways: 10-15% maximum
- Highway design: 5-8% maximum (varies by location)
- Railway design: 1-2% maximum
- Roof pitch: 16.7-100% (4:12 to 12:12 ratio)
- Drainage pipes: 1-2% minimum for proper flow
How to Use the Slope Grade Calculator
Our slope grade calculator is designed to help you convert between different measurements of slope: angles, percentages, and ratios. Here's how to use each calculator mode:
Angle to Grade
1. Enter an angle in degrees or use the slider to select a value
2. The calculator will automatically convert this to a grade percentage and ratio
3. The visual indicator shows the steepness of the slope
Grade to Angle
1. Enter a grade percentage or use the slider to select a value
2. The calculator will automatically convert this to an angle in degrees and a ratio
3. The visual indicator shows the steepness of the slope
Slope Calculator
1. Choose between "Rise over Run" (y/x) or "Run over Rise" (x/y) format
2. Enter values for the run (x) and rise (y)
3. The calculator will convert this to grade percentage, angle, and ratio
Frequently Asked Questions
Maximum 8.33% grade (1:12 ratio)
Typically 10-15% grade
Maximum 6-8% grade (varies by location)
Up to 10-15% grade
Typically 16.7-100% (4:12 to 12:12 ratio)
- Road and highway design
- Wheelchair ramp construction
- Drainage system planning
- Roof pitch calculation
- Landscape architecture
- Hiking trail difficulty assessment
- Ski slope classification
- Railway design
- Erosion control planning