Integral Calculator

A definite integral computes the net signed area between a function f(x) and the x-axis over an interval [a, b]. It is one of the two fundamental operations of calculus (the other being differentiation) and is the basis for computing areas, volumes, arc lengths, work, probability, and much more

The calculator uses the standard published formula for integral calc. Results are accurate to the precision of the inputs you provide. For financial, medical, or legal decisions, always verify with a qualified professional.

This calculator works with inches. You can enter values in the units shown — the calculator handles all conversions internally.

The core formula is: Definite integral ∫[a,b] f(x) dx = F(b) − F(a) where F is the antiderivative of f. Each step in the calculation is shown so you can verify the result manually.