Line Through Two Points Calculator

About this calculator

Given two points (x1, y1) and (x2, y2), the slope of the line through them is m = (y2 − y1) ÷ (x2 − x1), and once you have the slope, the y-intercept follows from plugging either point into the slope-intercept form y = mx + b and solving for b. This is the same point-slope method taught in every algebra course for turning two coordinates into a full linear equation.

Students use this to write the equation of a line as a standard algebra exercise, while it also comes up constantly outside the classroom: fitting a straight-line trend between two data points, like two years of sales figures to estimate a growth rate, calculating a rate of change in physics or economics, or setting up a linear conversion formula between two known reference values.

This calculator takes the coordinates of two points and returns the slope and y-intercept of the line passing through them, along with its full equation.