Three-Dimensional Distance Calculator

Quick answer

The 3D distance calculator finds the straight-line distance between two points (x₁, y₁, z₁) and (x₂, y₂, z₂) in space, with the coordinate differences and the midpoint.

Distance D
13
Δx
3
Δy
4
Δz
12
Midpoint – x
2.5
Midpoint – y
4
Midpoint – z
9

The 3D distance formula extends the Pythagorean theorem to space: drone flight paths, the length of a diagonal brace, distances between atoms or between objects in a 3D model.

How to use the Three-Dimensional Distance Calculator

  1. X₁
  2. Y₁
  3. Z₁
  4. X₂
  5. Y₂
  6. Z₂

Results update as you type, and everything is calculated in your browser.

How it works

Square the differences in each coordinate, add them and take the square root.

Inputs explained

Field What to enter
X₁ A number
Y₁ A number
Z₁ A number
X₂ A number
Y₂ A number
Z₂ A number

What each result means

  • Distance D = sqrt(([X₂] – [X₁])^2 + ([Y₂] – [Y₁])^2 + ([Z₂] – [Z₁])^2)
  • Δx = [X₂] – [X₁]
  • Δy = [Y₂] – [Y₁]
  • Δz = [Z₂] – [Z₁]
  • Midpoint – x = ([X₁] + [X₂])÷2
  • Midpoint – y = ([Y₁] + [Y₂])÷2
  • Midpoint – z = ([Z₁] + [Z₂])÷2

Example values

How the main result changes when X₁ changes and everything else stays at the example values above:

X₁ Distance D
0.5 13.1244
0.75 13.06
1 13
1.25 12.9446
1.5 12.8938
2 12.8062

Formula

D = √[(x₂ − x₁)² + (y₂ − y₁)² + (z₂ − z₁)²]

Worked example

Inputs — X₁: 1; Y₁: 2; Z₁: 3; X₂: 4; Y₂: 6; Z₂: 15.
Results — Distance D = 13; Δx = 3; Δy = 4; Δz = 12; Midpoint – x = 2.5; Midpoint – y = 4; Midpoint – z = 9.

Key terms

Euclidean distance
Straight-line distance.

Frequently asked questions

What is the distance between (1, 2, 3) and (4, 6, 15)?

√(9 + 16 + 144) = 13.

Does it work with negative coordinates?

Yes – differences are squared.

How is it related to the 2D formula?

It adds a (Δz)² term.

What is the diagonal of a box l × w × h?

√(l² + w² + h²) – the distance between opposite corners.

Sources

  1. OpenStax – Calculus Volume 3
  2. Wolfram MathWorld – Distance

Cite this calculator

Speedy Calculator. (2026). Three-Dimensional Distance Calculator. Speedy Calculator. https://speedycalculator.com/calculators/math/3d-distance/