Slope Calculator
Find the slope between two points, the line’s equation, its angle and grade.
Your inputs
Results
Slope (m)
2
- Equation
- y = 2x
- Angle with the x-axis
- 63.4349 °
- Grade (rise/run × 100)
- 200%
✓Exact calculation — rounded only for display
What this calculator does
Slope measures steepness as rise over run. From two points you also get the equation of the line through them, its angle with the x-axis and its grade as a percentage.
Formula and method
m = (y₂ − y₁) ÷ (x₂ − x₁); y = mx + b with b = y₁ − m x₁; angle = arctan(m)
Worked example
Calculated by this tool with its default inputs:
Inputs
- x₁: 1
- y₁: 2
- x₂: 4
- y₂: 8
Results
- Slope (m): 2
- Equation: y = 2x
- Angle with the x-axis: 63.4349 °
- Grade (rise/run × 100): 200%
How to read the results
A vertical line has an undefined slope.
Assumptions and limitations
- Grade expresses slope as a percentage.
Questions
What is a negative slope?
A line that falls from left to right.
Methodology and verification
- Result type
- Exact mathematical calculation (rounded only for display)
- Formula version
- 1.0
- Automated verification
- 3 reference and validation test cases, checked against independently computed values. The site cannot be built if any of them fail.
- Editorial review
- Awaiting human editorial review. The explanation was drafted with AI assistance; the formula and examples are verified by the automated tests above.
Privacy
Everything you enter is calculated in this browser and is not sent to Numerith or anyone else. Inputs are added to a share link only if you choose to include them. Privacy policy