All calculators and tools
Choose by subject and explore the available tools. All are free, work on your phone and show the calculation step by step.
Math
Percentage Calculator
Part of a value, discount, increase and percent change, with the math shown step by step.
Open tool →Rule of Three Calculator
Simple rule of three, direct or inverse, with the proportion set up and explained.
Open tool →Fraction Calculator
Add, subtract, multiply, divide, compare and simplify fractions, with mixed numbers and decimals.
Open tool →Scientific Calculator
Expressions with parentheses, powers, roots, logarithms, trigonometry and factorials, with an on-screen keypad.
Open tool →Quadratic Equation Calculator
Quadratic formula with delta, roots, vertex and step-by-step work, even when there are no real roots.
Open tool →Geometry
Area and Perimeter Calculator
Rectangle, square, triangle, circle, trapezoid, parallelogram and rhombus, with the formulas on display.
Open tool →Volume Calculator
Cube, box, cylinder, cone, sphere and pyramid, with volume, surface area and liters.
Open tool →Pythagorean Theorem Calculator
Find the hypotenuse or a leg of a right triangle, with angles and area as a bonus.
Open tool →Physics
Conversions
Daily Life
Date Difference Calculator
Days, months and years between two dates, business days, and how to add or subtract time periods.
Open tool →Average and Weighted Average Calculator
Simple average, weighted average, median, mode, standard deviation and the grade you still need to reach your target average.
Open tool →Grade Average Calculator
Yearly average by grading period, the grade you still need to pass, make-up exams and minimum attendance.
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