Arithmetic sequences, geometric series, harmonic numbers, and sum calculators. Browse our free sequences & series tools below — all calculators are instant, accurate, and require no sign-up.
Arithmetic Sequence Calculator — Calculate the nth term, sum of n terms, common difference, and generate arithmetic sequences with visual growth charts and partial sums.
Geometric Sequence Calculator — Calculate nth term, finite and infinite sums, common ratio, and visualize exponential growth or decay in geometric sequences.
Harmonic Mean Calculator — Calculate the harmonic mean of any set of numbers, compare with arithmetic and geometric means, and verify the AM-GM-HM inequality.
Harmonic Number Calculator — Compute the nth harmonic number H(n), partial sums, approximations using the Euler-Mascheroni constant, and generalized harmonic numbers.
Sum of Digits Calculator — Calculate the digital sum, digital root, iteration steps, and divisibility properties of any number in multiple bases.
Sum of Series Calculator — Compute partial sums of arithmetic, geometric, telescoping, p-series, and power sum series with convergence analysis and visualization.