Point-Slope Form Calculator (Free, With Steps)

Enter a point and a slope, or two points, and this calculator writes the line in point-slope form, slope-intercept form, and standard form. It shows every step and keeps answers as exact fractions.

Type whole numbers, decimals (1.5), or fractions (3/4). Results update as you type.

How to Use This Calculator

It’s built to be quick. Pick the tab that matches what you know, type your numbers, and read the results. You don’t have to press a button, because it updates as you type.

  • Point + Slope tab: enter the point’s x₁ and y₁, then the slope m. You can type the slope as a whole number, a decimal, or a fraction like 3/4.
  • Two Points tab: enter both points. The calculator finds the slope for you, then writes the equation.

How the Calculator Works

Under the hood it uses the point-slope formula, y − y₁ = m(x − x₁). When you give it two points, it first calculates the slope with m = (y₂ − y₁) / (x₂ − x₁), then substitutes. Because it works with exact fractions rather than decimals, you won’t see rounding errors creep in.

Output Formats

Every calculation returns three equivalent equations, so you can hand in whichever your assignment asks for:

  1. Point-slope form: y − y₁ = m(x − x₁)
  2. Slope-intercept form: y = mx + b
  3. Standard form: Ax + By = C, with integer coefficients

Want to see the method by hand? Read how to find point-slope form, work through ten solved examples, or learn how to convert between forms.

Frequently asked questions

How do you calculate point-slope form?
Take your slope m and a point (x₁, y₁), then substitute them into y − y₁ = m(x − x₁). The calculator above does it instantly and shows each step.
Can this calculator use two points?
Yes. Switch to the Two Points tab, enter both points, and it finds the slope first, then writes the point-slope equation for you.
What happens with an undefined slope?
If both points share the same x-value, the line is vertical and the slope is undefined. The calculator tells you this and gives the equation as x = a constant instead.
Does it show fractions instead of decimals?
It does. The calculator keeps answers as exact fractions, so a slope of one third shows as 1/3 rather than a rounded 0.333.
How do I convert the result to slope-intercept form?
You don’t need to do anything extra. Every result also lists slope-intercept form (y = mx + b) and standard form, so you can copy whichever one you need.

Want the method, not just the answer?