Plane Through a Point with a Normal Vector (3D)

Published on: May 10, 2026

This Plane Through a Point with a Normal Vector (3D) Calculator helps you find the equation of a plane in three-dimensional space from a given point and normal vector. Use the point as a known position on the plane and the normal vector to determine the plane’s orientation. Then substitute those values into the point-normal form and simplify to get the equation. It is a simple way to check answers, understand the method clearly, and practise 3D coordinate geometry step by step.

Step-by-step method

  1. Identify the point P(x₀, y₀, z₀) and the normal vector n = ⟨a, b, c⟩.
  2. Write the point-normal plane equation.
  3. Substitute values and simplify.

Formula:

a(x − x₀) + b(y − y₀) + c(z − z₀) = 0
ax + by + cz = d, where d = ax₀ + by₀ + cz₀

Example 1: (1,2,3),(2,-1,4)

Step 1 - Identify the point and normal components.

In this problem: Extract x₀, y₀, z₀ and a, b, c from the input.

x₀ = 1, y₀ = 2, z₀ = 3
a = 2, b = -1, c = 4

Step 2 - Write the point-normal plane equation.

In this problem: Use a(x − x₀) + b(y − y₀) + c(z − z₀) = 0.

a(x − x₀) + b(y − y₀) + c(z − z₀) = 0

Step 3a - Substitute values.

In this problem: Substitute your point and normal values into the formula.

2(x − 1) + -1(y − 2) + 4(z − 3) = 0

Step 3b - Expand.

In this problem: Expand and combine like terms.

−12 − y + 2x + 4z = 0

Step 3c - Write standard form.

In this problem: Rearrange into ax + by + cz = d.

−y + 2x + 4z = 12

Final answer: a(x-x0)+b(y-y0)+c(z-z0)=0 with a,b,c=(2,-1,4) and (x0,y0,z0)=(1,2,3)

Example 2: (1/2,0,-3),(3,2,-4)

Step 1 - Identify the point and normal components.

In this problem: Extract x₀, y₀, z₀ and a, b, c from the input.

x₀ =
1
2
, y₀ = 0, z₀ = -3
a = 3, b = 2, c = -4

Step 2 - Write the point-normal plane equation.

In this problem: Use a(x − x₀) + b(y − y₀) + c(z − z₀) = 0.

a(x − x₀) + b(y − y₀) + c(z − z₀) = 0

Step 3a - Substitute values.

In this problem: Substitute your point and normal values into the formula.

3(x −
1
2
) + 2(y − 0) + -4(z − -3) = 0

Step 3b - Expand.

In this problem: Expand and combine like terms.

27
2
− 4z + 2y + 3x = 0

Step 3c - Write standard form.

In this problem: Rearrange into ax + by + cz = d.

−4z + 2y + 3x =
27
2

Final answer: a(x-x0)+b(y-y0)+c(z-z0)=0 with a,b,c=(3,2,-4) and (x0,y0,z0)=(1/2,0,-3)