How this calculation works
The difference between the sums at n and n−1 is exactly n². This gives a direct check on the formula.
THE FORMULA
n(n+1)(2n+1)/6A worked example
1² + 2² + … + 10² = 385.
Good to know
An empty sum is zero.
Reference: NIST DLMF, Functions of Number Theory (opens in a new tab) ↗
Read the result
Add the squares from 1² through n² without listing each term.
The primary result is labeled “Sum of squares”. Keep the input definitions in view when comparing this result with another method.
Try a related calculation
An empty sum is zero.
For a related exercise, try the greatest common divisor.
A few questions, answered
How can I check the default inputs by hand?
1² + 2² + … + 10² = 385.
Which rule does this calculator apply?
n(n+1)(2n+1)/6