How to find a midpoint
Use this calculator to find the point halfway between two points in 2D or 3D. It averages matching coordinates using the midpoint formula. The calculation assumes a flat Cartesian plane or flat 3D space.
For 2D points, the formula is M = ((x1 + x2) / 2, (y1 + y2) / 2). For 3D points, add the third coordinate: M = ((x1 + x2) / 2, (y1 + y2) / 2, (z1 + z2) / 2).
Enter coordinates and choose a dimension
- Select 2D (x, y) or 3D (x, y, z).
- Enter the values for Point 1 and Point 2 in the visible coordinate fields.
- If you change between 2D and 3D, the current result is hidden and the displayed error is cleared.
Choose a unit label
Select one of the visible options: Unitless (plain coordinates), Millimeters (mm), Centimeters (cm), Meters (m), Kilometers (km), Inches (in), Feet (ft), Yards (yd), or Miles (mi).
The selector labels the result; it does not convert values. Express both points in the same unit before calculating.
Calculate, copy, download, or reset
- Click Calculate to show the midpoint, formula, and calculation steps.
- Review the displayed values, which are formatted to at most six decimal places.
- Click Copy result to copy the plain-text result. If clipboard access fails, the tool can show Could not copy - select and copy manually.
- Click Download result (.txt) to download the result as a plain-text file.
- Click Reset to clear the coordinate fields, return the unit to Unitless (plain coordinates), switch to 2D, and hide the result.
Input limits and coordinate assumptions
Enter signed decimal values, including positive, negative, zero, and other decimal values. The input parser does not accept scientific notation or a leading plus sign. Empty, invalid, or non-finite inputs are rejected. A coordinate with an absolute value greater than 1e12 is rejected as too large to calculate.
- Both points must use the same unit label; the calculator does not convert between units.
- In 2D mode, the calculation uses only x and y. It does not infer a missing z-coordinate.
- The tool calculates a straight-line midpoint in flat Cartesian coordinates. It is not intended for latitude/longitude map coordinates or calculations involving Earth's curvature.
Privacy and calculation behavior
The midpoint calculation runs in the page’s browser-side script. That calculation does not upload the coordinates you enter or make a calculation request.
Frequently Asked Questions
What is the midpoint formula?
For two 2D points (x1, y1) and (x2, y2), the midpoint is M = ((x1 + x2) / 2, (y1 + y2) / 2). It is the average of each corresponding coordinate.
How is the midpoint calculated in 3D?
For two 3D points (x1, y1, z1) and (x2, y2, z2), the midpoint is M = ((x1 + x2) / 2, (y1 + y2) / 2, (z1 + z2) / 2), extending the 2D formula with a third averaged coordinate.
Can coordinates be negative?
Yes. The calculator accepts signed decimal values, including positive, negative, zero, and other decimal values, subject to its input format and magnitude limit. Averaging works the same way regardless of sign.
What units does this calculator support?
You can choose Unitless (plain coordinates), Millimeters (mm), Centimeters (cm), Meters (m), Kilometers (km), Inches (in), Feet (ft), Yards (yd), or Miles (mi). The calculator labels the result but does not convert values, so both points must already use the same unit.
Does this calculator work for real-world map coordinates?
No. This tool computes the straight-line (Euclidean) midpoint on a flat plane or in flat 3D space from coordinates you provide. It does not account for Earth's curvature, elevation data, or GPS coordinate systems.