Calculation history
History stays in this browser through local storage.
| Name | Date | Case | Area | Actions |
|---|---|---|---|---|
| No saved calculations yet. | ||||
Compare two saved triangles
Formulas used
Triangle angle sum
Law of Sines
Law of Cosines
Heron's formula
Two sides and included angle
Radii
How to use this calculator
- Select the standard, coordinate, or surveying mode.
- Choose the input angle format and preferred output formats.
- Enter known values and leave unknown values blank.
- Use uncertainty fields when measurements include tolerances.
- Press Solve triangle to calculate every valid solution.
- Review the diagram, advanced geometry, centers, and detailed steps.
- Save, compare, copy, print, or export the completed calculation.
For SSA inputs, inspect every returned solution because two triangles may satisfy the same measurements.
Supported triangle cases
| Case | Known measurements | Main method | Special behavior |
|---|---|---|---|
| SSS | Three sides | Law of Cosines | Triangle inequality validation |
| SAS | Two sides and included angle | Law of Cosines | Unique triangle |
| ASA | Two angles and included side | Angle sum and Law of Sines | Unique triangle |
| AAS | Two angles and non-included side | Angle sum and Law of Sines | Unique triangle |
| SSA | Two sides and non-included angle | Law of Sines | Zero, one, or two triangles |
| Coordinates | Three vertex coordinates | Distance and determinant formulas | Centers and line equations |
Frequently asked questions
What is an oblique triangle?
An oblique triangle has no required right angle. It may be acute or obtuse.
Why can SSA return two answers?
A sine value can correspond to an acute angle or its supplement. Both may fit the supplied side lengths.
Can I mix feet, inches, and meters?
Yes. Choose a unit beside each side. The solver converts values internally before calculating.
How are triangle centers calculated?
The solver creates or uses coordinates, then calculates centroid, incenter, circumcenter, and orthocenter positions.
Does the solver detect right triangles?
Yes. A right result is classified even though the primary calculator targets oblique triangles.
How accurate are the results?
The solver preserves full floating-point precision internally. Display rounding affects only presented values.
What does the uncertainty estimate mean?
It approximates area sensitivity to side tolerances using numerical derivatives and root-sum-square propagation.
Can the diagram be exported?
Yes. Use the SVG button after solving. Printing can also save the complete report as PDF.
Is calculation history uploaded anywhere?
No. The history feature uses local browser storage on the current device.