Areas, volumes & perimeters for 2D and 3D shapes with precision — every formula shown, every result instant, and no ads getting in your way.
One tool for students checking homework, engineers sizing parts, and teachers building lessons.
Circle, Triangle (3 modes), Rectangle, Square, Rhombus, Parallelogram, Pentagon, Trapezoid.
Sphere, Cube, Cylinder, Rectangular Prism, Cone, Pyramid, Ellipsoid, Prism.
Solve triangles from base & height, three sides, or two sides & an angle — same for other shapes.
See exactly which formula produced your result, expandable right below the answer.
Every calculation is logged with date and time, so past work is never lost.
Comfortable in any light, matching your system theme or your preference.
mm, cm, m, km, in, ft, yd, mi — pick what your project actually uses.
Every calculator, every feature — no paywalls, no interruptions.
The same short path, whichever of the 16 shapes you need.
Tap any of the 16 icons in the sidebar — 2D on one side, 3D on the other.
Type in the values the shape needs — radius, sides, diagonals, or an angle.
Area, volume, perimeter and the exact formula used, all in real time.
Every calculator includes the formulas behind it.
Each calculator ships with a formula reference, right where you need it.
I stopped rebuilding the same volume formulas in my notes app. This has every shape from my statics course in one place, with the formula right there to double-check my work.
Between site visits and studio reviews, I need fast, correct surface area and volume figures. The formula reference means I can explain the number, not just report it.
I project the triangle calculator on the board and let students see the formula update live as we change the inputs. It's become a regular part of how I teach geometry now.
Free to download, free to use, no ads — get started in under a minute.
Download on Google Play