Slope Calculator
Enter Rise and Run to instantly calculate slope percentage, angle, ratio, and slope length. Unit-independent — just use the same unit for Rise and Run.
Rise and Run slope calculator
Inputs
Unit-independent — just use the same unit for Rise and Run.
Results
Slope—
Ratio—
Angle—
Slope length—
Slope diagram
See the slope as you calculate
The diagram updates as you enter Rise and Run, so you can see the slope, angle and direction alongside the calculated values.
Examples
Positive slope
| Rise | 2 | Run | 10 |
|---|---|---|---|
| Slope | 20% | Angle | 11.31° |
| Ratio | 1:5 | Slope length | 10.20 |
Negative slope
| Rise | -2 | Run | 10 |
|---|---|---|---|
| Slope | -20% | Angle | -11.31° |
| Ratio | 1:5 (negative) | Slope length | 10.20 |
Frequently asked questions
Divide Rise by Run. Multiply by 100 for slope percentage. The calculator also converts the result to an angle and ratio.
A 1:5 slope means the elevation changes by 1 unit for every 5 units of horizontal distance. This equals a 20% slope and an angle of about 11.31°.
Yes. The calculator is unit-independent. Just use the same unit for both Rise and Run.
A negative slope means the elevation falls as you move along the Run. For example, Rise −2 and Run 10 gives a −20% slope and an angle of about −11.31°.
Very shallow slopes can become almost invisible when drawn proportionally on a screen. In those cases, the diagram is enlarged for readability while the calculated values remain accurate.
Slope formulas
Rise is the vertical change. Run is the horizontal distance. Use the same unit for both.
Slope % = (Rise ÷ Run) × 100Angle = arctan(Rise ÷ Run)Slope length = √(Rise² + Run²)