Triangle Area from Coordinates Calculator
Calculate triangle area from coordinates with explicit inputs and a worked example.
Formula
- Use the units shown beside each field.
- Results update automatically whenever you change an input.
- Displayed values use up to four decimal places, or scientific notation for very small or large numbers. Calculations use standard floating-point arithmetic; exact integer and fraction tools identify their own precision rules.
Example Calculation
- x₁: 0
- y₁: 0
- x₂: 4
- y₂: 0
- x₃: 0
- y₃: 3
Vertices (0,0), (4,0), (0,3) enclose 6 square units.
Frequently asked questions
How do I use this calculator?
Enter x₁, y₁, x₂, y₂, x₃, y₃. The result updates automatically. Use Reset to restore the example values.
What method does it use?
A = |(x₂−x₁)(y₃−y₁) − (y₂−y₁)(x₃−x₁)|/2. Follow the units and definitions shown with the inputs to apply this relationship consistently.
Why might a rounded result differ?
The calculation keeps full numeric precision internally, then rounds the displayed result. Rounding intermediate steps by hand can produce a slightly different answer.
Are my inputs saved online?
No. This calculator processes your inputs in your browser. A recently used list stores only calculator names on this device, not your entered values.
Check the assumptions and units before using this result. Read about calculation methods.