Number Sequence Calculator
Work with arithmetic (constant difference) and geometric (constant ratio) sequences: find the nth term, the sum of the first n terms, and a preview of the sequence.
Inputs explained
- Sequence type — Arithmetic adds the same difference each step; geometric multiplies by the same ratio.
- First term — The first term of the sequence.
- Common difference — The amount added each step (arithmetic sequences).
- Common ratio — The factor multiplied each step (geometric sequences).
- Term number n — Which term to compute (and how many terms to sum).
How to use it
- Fill in the fields above — each input has a hint describing exactly what to enter
- Press Calculate to get your result instantly, right on this page
- Copy the result, save the tool to favorites, or share and embed it anywhere
Understanding the result
Example: For an arithmetic sequence starting at 5 with difference 3, the 10th term is 5 + 9 × 3 = 32 and the sum of the first 10 terms is 185.
Frequently asked questions
What's the difference between the common difference and the common ratio fields? Common difference is used only for arithmetic sequences (added each step), while common ratio is used only for geometric sequences (multiplied each step) — you fill in whichever matches the sequence type you select.
Can the sum formula be used for an infinite geometric sequence? No, this calculator sums a finite number of terms (n terms); an infinite geometric sum only converges when the common ratio's absolute value is less than 1, which requires a separate formula.
Is the Number Sequence Calculator free to use? Yes — it is completely free, with no sign-up, no download and no usage limits. You can use it as often as you need.
Is my data private? Yes. The calculation runs entirely in your browser — the values you enter are never sent to our servers, stored or shared with anyone.
What information do I need? Just the following: Sequence type, First term, Common difference, Common ratio, Term number n. Each field includes a hint explaining exactly what to enter.
Can I use it on my phone? Yes — the tool is fully responsive and works on any device, and the same calculator is available in the EasyWorkCalcs mobile app.
Privacy
Everything you enter into the Number Sequence Calculator is processed entirely in your browser. Nothing is uploaded, stored or shared — your data stays on your device.