Rise / Run Calculator
Compute slope, gradient, and hypotenuse length from two point coordinates. Useful for ramps, roofs, and terrain analysis.
Point 1
Point 2
Result
About rise, run, and slope
The rise-run method expresses slope by the vertical change ("rise") relative to horizontal change ("run") between two points. Slope = rise/run, typically shown as a ratio (1:10), percentage (10%), or angle (5.71°). The hypotenuse is the direct slope length, computed by Pythagoras.
This basic geometric computation is foundational in road grading, accessibility ramp design, roof pitch specification, and terrain profiling. The ADA (Americans with Disabilities Act) requires ramps ≤ 8.33% slope; roof pitches are classified as low (<33%), conventional (33-58%), or steep (>58%).
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Practical use cases
Verifying accessibility ramp compliance (max 1:12 or ~8.33% in most jurisdictions).
Planning driveway and road gradients before construction.
Computing rafter lengths from roof rise/run specifications.
Analyzing terrain slope between two survey points for erosion or drainage studies.
Frequently asked questions
What is a standard accessibility ramp slope?
ADA standard in the US: 1:12 maximum (8.33%). Many European countries use 1:20 (5%) as preferred maximum. Check local regulations.
How do I convert percentage to degrees?
Degrees = arctan(percentage/100). 100% = 45°. 10% ≈ 5.71°. This tool shows both automatically.
What if my run is zero?
A zero run means a vertical line, which has undefined slope (division by zero). The tool reports an error; use a small non-zero run instead.
Are percentages and gradients the same thing?
Yes. Percentage is slope × 100. Gradient in railway use is often expressed as 1:N (reciprocal of slope fraction).
Related tools
See slope/gradient calculator for 4-way conversions and roof pitch calculator for building-specific terms.