A Practical SSS Angle Tool
This calculator helps when all three sides are known. It uses the law of cosines to find each missing angle. It also checks whether the sides can form a real triangle. That check is important. A small input mistake can create impossible geometry.
Why The Method Works
The law of cosines connects one angle with the three sides around it. For angle A, side a sits opposite the angle. Sides b and c meet at that angle. The formula rearranges the side relationship and isolates the cosine value. Then the inverse cosine gives the angle. The same method is repeated for angles B and C.
Useful Extra Results
A good SSS calculator should do more than show angles. This tool also returns perimeter, semiperimeter, area, height values, medians, inradius, and circumradius. These values help in construction sketches, classroom problems, surveying notes, craft planning, and layout checks. The classification note explains whether the triangle is acute, right, obtuse, equilateral, isosceles, or scalene.
Accuracy And Rounding
The calculator uses decimal precision chosen by the user. More decimals give finer results. Fewer decimals make reports easier to read. Very tiny differences may appear when sides are long or decimals are high. That is normal because angle calculations use inverse trigonometric functions.
How To Read The Output
Angles are shown in the selected unit. The sum should be close to 180 degrees, or pi radians. Area is found with Heron's formula. The perimeter is the total outside length. Heights show the perpendicular distance to each side. Medians show the line from each vertex to the midpoint of the opposite side.
Best Use Cases
Use this page when you know three side lengths. Do not use it when only two sides are known. Use consistent units for every side. If sides are entered in meters, area becomes square meters. If sides are entered in feet, area becomes square feet. The exported files are helpful for records, homework, estimates, and review notes.
Input Tips
Measure carefully before entering numbers. Avoid mixing inches with centimeters. Use the same scale for copied plans. When possible, keep original notes nearby. This makes checks easier and prevents typing errors during repeated calculations for every project.