Slope Calculator
Find the slope, angle and equation of the line through two points.
What the Slope Calculator does
Slope is rise over run: how much the line climbs for each unit it moves right. Positive slopes rise, negative slopes fall, zero is flat, and a vertical line has no defined slope because the run is zero.
Formula
m = (y₂ − y₁) ÷ (x₂ − x₁)y = mx + bPerpendicular slope = −1 ÷ m
Inputs explained
| Input | Unit | Required | Notes |
|---|---|---|---|
| x₁ | number | Yes | — |
| y₁ | number | Yes | — |
| x₂ | number | Yes | — |
| y₂ | number | Yes | — |
How to use it
- Enter x₁, y₁, x₂ and y₂.
- Select Calculate.
Worked example
A wheelchair ramp rises 0.5 m over a 6 m run.
- x₁, y₁
- 0, 0
- x₂, y₂
- 6, 0.5
Slope 0.0833, a grade of 8.33% — steeper than the 1:12 (8.33%) accessibility limit allows only just.
Frequently asked questions
What does a slope of zero mean?
A horizontal line. Its y value never changes. A vertical line is the opposite case and has an undefined slope.
How do I convert slope to a percentage grade?
Multiply by 100. A slope of 0.05 is a 5% grade, meaning 5 units of rise per 100 of run.