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Length of a Line Segment Calculator.

Find the distance between two Cartesian points.

On-device calculationNo signup
01

Set your values

Results update as you type.

Length: 5 units

Length

0.000000units
Δx: 3 units

Δx

0.000000units
Δy: 4 units

Δy

0.000000units

Results update automatically as you type.

Use Cases

Geometry homework and math practice

Quickly verify the length of a line segment between two points when solving geometry problems or practicing coordinate geometry.

Example: Find the distance between (1, 2) and (4, 6) to check your answer.

Mapping and navigation planning

Estimate straight-line distances between two locations on a Cartesian grid, useful for planning routes or understanding spatial relationships.

Example: Measure the direct distance between two landmarks on a city map.

Frequently Asked Questions

How do I use the Length of a Line Segment Calculator?
Enter the x and y coordinates for the first point (x₁, y₁) and the second point (x₂, y₂) in the corresponding fields. The calculator will compute the Euclidean distance between them, which is the length of the line segment connecting the two points.
What formula does this calculator use?
It uses the distance formula derived from the Pythagorean theorem: distance = √((x₂ - x₁)² + (y₂ - y₁)²). This gives the straight-line distance between the two points in the same units as the coordinates.
Can I use negative coordinates?
Yes, the calculator accepts negative values for x and y coordinates. The distance formula squares the differences, so negative coordinates work perfectly and yield a positive distance.

Tips & Common Mistakes

Tips

  • Double-check that you enter the coordinates in the correct order: x₁, y₁ for the first point and x₂, y₂ for the second point.
  • The result is always a non-negative number, representing the straight-line distance in the same units as your coordinates.
  • If you need the distance between points in 3D space, this calculator is not applicable; it only works for 2D Cartesian coordinates.
  • For a quick mental check, remember that the distance is the hypotenuse of a right triangle with legs equal to the differences in x and y.

Common Mistakes to Avoid

  • Swapping the x and y coordinates for a point, which can lead to an incorrect distance if the points are not symmetric.
  • Forgetting to square the differences before adding them, which would give the Manhattan distance instead of the Euclidean distance.
  • Entering coordinates with commas or parentheses (e.g., '1,2' or '(1,2)') instead of just numbers, which may cause errors.

Last updated: August 13, 2026