How to use sigma notation
Enter an expression in a one-letter index, then enter inclusive integer bounds. For example, Σ n from 1 through 100 has 100 terms and equals 5050; Σ n² from 1 through 10 equals 385. Multiplication may be explicit (2*n) or adjacent (2n). The output displays the first terms and final terms so you can inspect the expansion.
Supported expressions and limits
The bounded parser supports +, −, ×, ÷, powers, parentheses, sqrt, abs, sin, cos, tan, exp, ln, log (base 10), pi, and e. Trigonometry uses radians. A sum may contain at most 2,000 terms. Undefined real-domain terms are rejected rather than included as NaN or Infinity. This is numeric summation, not a symbolic closed-form solver.
Different from adding a list
The Sum Calculator adds numbers you provide. This calculator generates terms by evaluating one indexed expression at every integer in the chosen range.
Privacy
Inputs and results remain in this browser tab; this page does not submit, persist, or encode your expression in the URL.