Geometric Series Sum
The finite geometric sum combines a series of repeatedly scaled quantities. A ratio of one is handled as repeated addition of the same term.
Geometric Series Sum
Sequences · 3 inputs
How to use this calculator
- Enter first term in number.
- Enter common ratio in number.
- Enter number of terms in count.
- Select Calculate and keep the output unit with the answer.
Before you use the answer
Choose the reference quantity before interpreting the number. A ratio, a percentage and a percentage-point difference may use the same observations while answering different questions. For recorded data, keep the original values beside the summary so an unexpected result can be traced back to its inputs.
This is a finite sum, not the infinite-series formula. Negative ratios alternate signs.
Does it save my inputs?
No calculation history is stored by this website. The calculator works locally in your browser. See the privacy policy for hosting and contact details.
Why might a result be approximate?
Measurement uncertainty, ideal-model assumptions and floating-point rounding can all matter. Displaying more digits does not improve the original measurement.