Construction geometry
Slope grade and rise run
Convert measured rise and horizontal run to grade, angle and sloping length, or find rise from a supplied grade.
Your inputs
Complete the fields for your selected method. Zero means intentionally zero, not unknown. Currency selection labels amounts; it does not convert exchange rates.
How this calculation works
grade percent = 100 × rise / horizontal run; angle = atan(rise / run); sloping length = sqrt(run² + rise²)
Measurement arithmetic for the stated ideal shape. Verify dimensions and assumptions at the site. No structural sizing, code compliance, safe load, stair approval, accessibility certification or boundary survey is supplied. Horizontal run differs from sloping surface length. Negative rise indicates descent. A flat slope gives zero grade and angle. The tool does not select a drainage slope or establish ramp, roof or accessibility compliance.
What information do I need?
Use records for the same job, equipment or accounting period. Only the fields for your selected entry method are required. An unknown amount is not zero.
Input definitions and where to find them
- Which slope information do you have?: Use a measured value or an explicit assumption for the stated geometry; check the selected entry method and units.
- Horizontal run (ft): Measure the stated distance and select its unit. Feet, inches and meters are supported. A perpendicular height is not a sloping length.
- Signed rise (negative for downward) (ft): Measure the stated distance and select its unit. Feet, inches and meters are supported. A perpendicular height is not a sloping length. Used with: Rise and horizontal run.
- Signed grade (%): Use a measured value or an explicit assumption for the stated geometry; check the selected entry method and units. Used with: Grade percent and horizontal run.
Use the Where to find this value controls beside the inputs for available work-it-out helpers. Estimates remain your assumptions; a helper does not verify the source figures.
Worked example
Example amounts use US dollars (USD).
Example answer: Slope grade is 5.0000 % for the illustrative inputs below.
Example inputs
- Which slope information do you have?: Rise and horizontal run
- Horizontal run: 20.00 ft
- Signed rise (negative for downward): 1.00 ft
- Slope grade
- 5.0000 %
- Slope angle above horizontal
- 2.8624 degrees
- Signed rise
- 1.0000 ft
- Sloping length
- 20.0250 ft
- Rise per 12 inches of horizontal run
- 0.6000 in / 12 in
These illustrative values are not recommended rates or industry averages. Replace every example input with your own figures.
Use the result well
Convert measured rise and horizontal run to grade, angle and sloping length, or find rise from a supplied grade.
Keep inputs on the same scope and time basis. Calculations retain precision internally; displayed values generally round to two decimal places, with extra precision for very small values and whole-unit rounding where required. Economic comparisons describe your supplied assumptions and do not guarantee future results.
This tool provides business arithmetic. It does not approve engineering designs, establish legal or tax treatment, select equipment or certify safe operating conditions.