Calculus is the mathematics of change and accumulation — the derivative tells you how fast something is changing right now, and the integral tells you how much has piled up in total. The derivative of x² is 2x: at x = 3 the function is climbing at a slope of 6. The integral of 2x from 0 to 3 is 9: the total area under that slope curve. These two operations are inverses, linked by the Fundamental Theorem of Calculus, which is why the same toolkit solves both. Physicists get velocity from position (derivative) and distance from velocity (integral); economists get marginal cost and total cost the same way; machine learning optimizes by following derivatives downhill. The power rule — bring down the exponent, subtract one — handles most polynomials students meet. This calculator evaluates calculus expressions for you: enter your values in the Variable A and Variable B fields and read the Result. If you are just starting, master the power rule first; it unlocks the majority of homework problems.

With the pre-filled defaults — Variable A 10, Variable B 5 — the Calculus Calculator returns Result 50.0000. Change any input and those results update instantly, so you can see exactly how each number you enter moves the answer.