Area of a Triangle Calculator
⬛ Area & perimeter (2D). Use the Area of a triangle (two sides and angle) formula to find area, side a, side b, angle c between them: pick the value you want, type the others, and the answer updates as you go.
Pick the ○ next to the value you want to find, fill in the others, and it solves as you type.
What each letter means
| Quantity | Unit |
|---|---|
| Area | cm² |
| Side a | cm |
| Side b | cm |
| Angle C between them | ° |
Worked example
Find the area when Side a = 5 cm, Side b = 6 cm, Angle C between them = 60 °.
Using A = 1/2 ab sin C: Area = 12.99 cm².
Frequently asked questions
What is the formula for Area of a triangle (two sides and angle)?
A = 1/2 ab sin C.
What do the letters stand for, and what units are used?
Area in cm², Side a in cm, Side b in cm, Angle C between them in °.
How do you calculate area?
Put the values into A = 1/2 ab sin C. For example, with Side a = 5 cm, Side b = 6 cm, Angle C between them = 60 °, area = 12.99 cm².
Can I solve for a different value?
Yes. In the calculator above, pick the circle next to any value (area, side a, side b, angle c between them) and fill in the others: it rearranges the formula for you.
