Calculate Midpoint Between Two Numbers- Formula and Examples

What Is a Midpoint?

The midpoint between two numbers is exactly what it sounds like—the number sitting precisely in the middle. It's not an approximation or an estimate. It's the exact center point on a number line.

Mathematically, it's the average of two values. Add them together, divide by two, and you get the midpoint.

The Midpoint Formula

Here's the formula:

Midpoint = (a + b) ÷ 2

Where a is the first number and b is the second number.

That's it. No fancy math involved. You don't need calculus, algebra tricks, or anything complicated. Just basic arithmetic.

How to Calculate the Midpoint (Step by Step)

Method 1: Simple Addition and Division

Follow these steps:

  1. Take your first number
  2. Add your second number to it
  3. Divide the sum by 2

Method 2: Find the Distance and Halve It

Alternative approach:

  1. Subtract the smaller number from the larger number
  2. Divide that difference by 2
  3. Add the result to the smaller number

Both methods give you the same answer. Use whichever feels faster.

Midpoint Examples

Example 1: Whole Numbers

Find the midpoint between 4 and 10.

Step 1: 4 + 10 = 14
Step 2: 14 ÷ 2 = 7

Midpoint = 7

Verify: The distance from 4 to 7 is 3. The distance from 7 to 10 is 3. The midpoint is correct.

Example 2: Negative Numbers

Find the midpoint between -6 and 4.

Step 1: -6 + 4 = -2
Step 2: -2 ÷ 2 = -1

Midpoint = -1

Example 3: Decimals

Find the midpoint between 2.5 and 7.5.

Step 1: 2.5 + 7.5 = 10
Step 2: 10 ÷ 2 = 5

Midpoint = 5

Example 4: Fractions

Find the midpoint between 1/4 and 3/4.

Step 1: 1/4 + 3/4 = 1
Step 2: 1 ÷ 2 = 1/2

Midpoint = 1/2

Midpoint vs. Average vs. Median

People confuse these three terms all the time. Here's the difference:

Term Definition Example
Midpoint Exact center between two values Midpoint of 2 and 8 is 5
Average Sum divided by count (same math as midpoint for two numbers) Average of 2 and 8 is 5
Median Middle value in a sorted list Median of [2, 5, 8, 12, 20] is 8

For exactly two numbers, midpoint and average are mathematically identical. The median is a different concept entirely and only matches when dealing with two values.

Midpoint Formula on a Coordinate Plane

In geometry, you often need the midpoint between two points. The formula extends to two dimensions:

Midpoint = ((x₁ + x₂) ÷ 2, (y₁ + y₂) ÷ 2)

Find the midpoint between points (2, 3) and (8, 7).

x-coordinate: (2 + 8) ÷ 2 = 5
y-coordinate: (3 + 7) ÷ 2 = 5

Midpoint = (5, 5)

Where You Actually Use This

Quick Reference: Midpoint Calculator

If you need to find midpoints regularly, here's a quick mental shortcut:

Common Mistakes to Avoid

Bottom Line

The midpoint formula is (a + b) ÷ 2. Add your two numbers, divide by two. That's the exact center. No shortcuts, no tricks, no complicated math.

If you're working with coordinates, apply the formula separately to x and y values. That's the only difference.