geometry calculator

Triangle Area From Coordinates Calculator

Keep this page handy for situations where a hand calculation would be slow or easy to miscopy around triangle area from coordinates.

Important Use Notice

Informational calculator only. Verify important outputs independently before legal, tax, medical, engineering, safety-critical, contractual, employment, or compliance use.

Estimate

Enter job values, review the estimate, then use the decision hints before ordering or quoting.

Estimate Results

Enter values to see the result.

Formula

area = |x1(y2-y3) + x2(y3-y1) + x3(y1-y2)| / 2

The shoelace pattern converts vertex coordinates into area without needing side lengths first.

Example

X1 0, Y1 0, X2 4, Y2 0, X3 1, Y3 3 gives Area 6. 00.

Check

Using the right formula with the wrong measurement label or axis.
Switching between degrees and raw ratios without noticing the change.

Next Step