# Slope Calculator

URL: https://speedycalculator.com/calculators/math/slope/
Last updated: 2026-10-25

> The slope calculator finds the slope of the line through two points, its angle, percentage grade, y-intercept and the equation y = mx + b.

## Inputs

- x₁
- y₁
- x₂
- y₂

## Results

- Slope (m)
- y-intercept (b)
- Angle of incline
- Grade

## Formula

```
m = (y₂ − y₁) ÷ (x₂ − x₁)
b = y₁ − m x₁
```

## Explanation

Slope measures steepness: rise over run. It is used for graphs, roads, roofs and ramps.

### How to use the Slope Calculator

- **x₁**
- **y₁**
- **x₂**
- **y₂**

Results update as you type, and every field accepts the units shown in its menu.

### How it works

Divide the change in y by the change in x. The intercept follows by substituting one point.

### Inputs explained

FieldWhat to enterx₁A numbery₁A numberx₂A numbery₂A number

### What each result means

- **Slope (m)** = ([y₂] - [y₁])÷([x₂] - [x₁])
- **y-intercept (b)** = [y₁] - [Slope (m)]×[x₁]
- **Angle of incline** = deg(atan([Slope (m)]))
- **Grade** = [Slope (m)]×100

### Example values

How the main result changes when **x₁** changes and everything else stays at the example values above:

x₁Slope (m)11.61.51.7778222.52.285732.666744

## Worked example

Inputs — x₁: 2; y₁: 3; x₂: 6; y₂: 11.

Results — **Slope (m) = 2**; y-intercept (b) = -1; Angle of incline = 63.4349 °; Grade = 200 %.

## Key terms

- **Rise over run**: Vertical change divided by horizontal change.

## FAQ

**What does a negative slope mean?**
The line falls from left to right.

**What is the slope of a vertical line?**
Undefined, because x does not change.

**What formula does the Slope Calculator use?**
m = (y₂ − y₁) ÷ (x₂ − x₁).