Free Slope Calculator Online
This free online slope calculator finds the slope, y-intercept, line equation, distance, and angle between any two points on a coordinate plane.
Two Points
Slope (m)
Enter two points above
How the Slope Calculator Works
The slope calculator uses the formula m = (y2 − y1) / (x2 − x1) to find the slope between two points. Enter the coordinates of point 1 (x1, y1) and point 2 (x2, y2) and the slope calculator instantly computes the slope, y-intercept, and full line equation.
For points (2, 3) and (6, 11): slope = (11−3)/(6−2) = 8/4 = 2. The y-intercept is 3 − 2×2 = −1. So the equation is y = 2x − 1. The slope calculator also computes the distance between points using the Pythagorean theorem: d = √((x2−x1)² + (y2−y1)²).
The slope calculator handles all special cases: horizontal lines (slope = 0), vertical lines (undefined slope), and negative slopes (line goes downward). It also shows the angle of inclination in degrees using arctan(m).
Slope in Real Life
Slope appears everywhere: a road's grade is its slope as a percentage. A 6% grade rises 6 feet per 100 feet of horizontal distance. The slope calculator converts between these formats.
In economics, slope represents rate of change — how much one variable changes per unit of another. In physics, slope on a distance-time graph gives velocity. On a velocity-time graph, slope gives acceleration. The slope calculator helps visualize these relationships.
Architects use slope for roof pitch, drainage grades, and ramp angles. ADA-compliant ramps require a slope no steeper than 1:12 (about 8.3%). The slope calculator can verify compliance by entering the rise and run coordinates.
Tips for Using the Slope Calculator
Point Order Does Not Matter
The slope calculator gives the same slope regardless of which point you enter first. Swapping points changes the sign of both numerator and denominator.
Check the Visualization
The slope calculator shows an SVG graph of the line through your two points. This visual check helps catch coordinate entry errors.
Vertical Lines
If x1 = x2, the slope is undefined (vertical line). The slope calculator detects this case and displays the equation as x = constant.
Use for Rise/Run Problems
Enter (0, 0) as point 1 and (run, rise) as point 2. The slope calculator gives the grade and angle directly.
Frequently Asked Questions
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