Sum of Integers Calculator
Calculate the sum of all integers from 1 to n using the Gauss formula.
Formula: S = n × (n + 1) / 2
About Sum of Integers Calculator
Sum of Integers Calculator is a free online calculator that gives you an instant, accurate result as you type. Calculate the sum of all integers from 1 to n using the Gauss formula.
The calculation uses the standard formula S = n × (n + 1) / 2 and updates live with every change to the inputs. Everything runs client-side in your browser — fast, private, and free to use as often as you like.
The result n(n+1)/2 is also called the nth triangular number, because that many dots can be arranged into a triangle.
Frequently Asked Questions
Is Sum of Integers Calculator free to use?
Yes. Sum of Integers Calculator is completely free, with no sign-up, no downloads, and no usage limits. You can use it as many times as you like on any device with a web browser.
How accurate is this calculator?
The calculator applies the standard formula (S = n × (n + 1) / 2) with full floating-point precision and rounds only the displayed result. For most practical purposes the results are exact.
What is the sum of 1 to 100?
5050. Using the formula: 100 × 101 / 2 = 5050 — the sum a young Carl Friedrich Gauss reportedly computed in seconds.
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