Calculus Calculators
Numerical Integration Calculator
Approximate a definite integral by trapezoidal, midpoint or Simpson's rule.
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What is Numerical Integration?
Numerical integration approximates the area under a curve by summing simple strips. The trapezoidal and midpoint rules use straight edges; Simpson's rule fits quadratics and is exact for polynomials up to degree 3.
How it works
The chosen rule is applied at N intervals and again at 2N, and the difference between them is reported as the error estimate — a direct, checkable measure of convergence. Simpson's rule is forced to an even interval count, which the page also states.
- Enter your input. Type or paste your input into the field above — the tool responds instantly.
- Review the result. Output updates live as you type. Everything runs entirely in your browser.
- Copy or download. Use the Copy button to grab the result, or Download to save it as a file.
Examples
Realistic sample
Type or paste any realistic input — the tool computes the result locally and instantly.
Common mistakes
Expecting a server round-trip
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