Maths & numbers

Infinite geometric series sum calculator

Find the limiting total of a convergent geometric series.

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Behind the numbers

How this calculation works

The closer the ratio is to magnitude one, the more terms it takes for partial sums to approach the limit.

THE FORMULAS = a/(1−r) when |r| < 1

A worked example

12 + 3 + 0.75 + … sums to 16.

Good to know

A nonzero geometric series converges only for |r| < 1.

Read the result

Find the limiting total of a convergent geometric series.

The primary result is labeled “Infinite sum”. Keep the input definitions in view when comparing this result with another method.

Try a related calculation

A nonzero geometric series converges only for |r| < 1.

For a related exercise, try the quadratic equation solver.

A few questions, answered

How can I check the default inputs by hand?

12 + 3 + 0.75 + … sums to 16.

Which rule does this calculator apply?

S = a/(1−r) when |r| < 1

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