Dot Product Calculator
Dot product calculator
Calculate scalar dot product for 2D or 3D vectors.
Result
21
Uses A·B = AxBx + AyBy + AzBz.
Auto
math
Flow
- Select 2D or 3D vectors.
- Enter components for vector A and vector B.
- Read scalar dot product and interpret sign and magnitude.
Example
Worked example: A = (2,1,3), B = (4,-2,5)
- 1 Multiply corresponding components.
- 2 Add products: 2×4 + 1×(-2) + 3×5.
- 3 Total is 21.
Dot product equals 21.
How
- Select 2D or 3D vectors.
- Enter components for vector A and vector B.
- Read scalar dot product and interpret sign and magnitude.
Avoid
- Using cross-product determinant instead of pairwise multiplication.
- Dropping z component in 3D mode.
Checks
Best fit
Dot Product Calculator is built for compute dot product for 2d or 3d vectors. If Dot Product Calculator does not match the input scope, compare the answer with a second method.
Input check
Match the entered values to this rule before copying the answer: A·B = AxBx + AyBy (+ AzBz).
Sanity check
For Dot Product Calculator, use the worked example as a quick benchmark: Dot product equals 21. If the dot product calculator answer is far away, check whether an input, unit, or mode changed.
Before copying
Review this common issue first: using cross-product determinant instead of pairwise multiplication.
FAQ
What if dot product is zero?
Vectors are orthogonal when both are non-zero and dot product is zero.
Can dot product be negative?
Yes. Negative values indicate an obtuse angle between vectors.
Is this matrix multiplication?
No. This tool computes vector inner product only.
Switch
Switch12
No match.