Midpoint Formula with Examples

The midpoint formula finds the point exactly halfway between (x₁, y₁) and (x₂, y₂): M = ((x₁ + x₂) ⁄ 2, (y₁ + y₂) ⁄ 2). You just average the x’s and average the y’s.

Theorems P₁P₂d

Distance & Midpoint

The distance between two points on a coordinate plane is the Pythagorean theorem applied to the horizontal and vertical gaps.

Distance
d = √((x2 − x1)2 + (y2 − y1)2)
Midpoint
M = ((x1 + x2) ⁄ 2, (y1 + y2) ⁄ 2)
Slope
m = (y2 − y1) ⁄ (x2 − x1)
  • (x₁, y₁) first point
  • (x₂, y₂) second point
Download PDF sheetPDF · A4 · 1 page · 136 KB

Example 1

Find the midpoint of (2, 3) and (8, 11).

  • x = (2 + 8) ÷ 2 = 5
  • y = (3 + 11) ÷ 2 = 7
  • M = (5, 7)

Example 2: with negatives

Find the midpoint of (−4, 6) and (2, −10).

  • x = (−4 + 2) ÷ 2 = −1
  • y = (6 + (−10)) ÷ 2 = −2
  • M = (−1, −2)

Example 3: find a missing endpoint

M = (3, 5) is the midpoint of A(1, 2) and B. Find B.

  • (1 + x) ÷ 2 = 3, so x = 5
  • (2 + y) ÷ 2 = 5, so y = 8
  • B = (5, 8)
Live calculator

Try the distance and midpoint calculator

P₁P₂d

Try it yourself

Find the midpoint of (0, 0) and (7, −3).

Show the answer

M = (3.5, −1.5)

The distance and slope formulas are on the distance and midpoint formulas page. See also our distance formula guide.

Download PDFPDF · A4 · 1 page · 136 KB

Midpoint formula: FAQ

What is the midpoint formula?

M = ((x₁ + x₂) ⁄ 2, (y₁ + y₂) ⁄ 2).

How do I find an endpoint from the midpoint?

Double the midpoint and subtract the known endpoint: x₂ = 2Mx − x₁ and y₂ = 2My − y₁.

Can the midpoint have decimals?

Yes. If the sum is odd, the midpoint is a half, such as 3.5.

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