Annuity Calculator
A clean, responsive tool to project a future balance from a starting principal, recurring contributions, and a constant annual growth rate. Choose whether contributions occur at the begin or end of each period.
Your initial lump sum invested at time 0.
Contribution made once per year. With begin, it’s added every January; with end, every December.
Contribution made each month. With begin, it’s added at the start of the month; with end, at the end.
Choose contribution timing (annuity due vs ordinary annuity).
Average annual return. You can enter a percent or decimal (e.g., 6 or 0.06).
Projection horizon in years (e.g., 20 years). Internally calculated in months.
Use sample: 10k + 6k/yr + 300/mo, 6% for 20y (begin)
Use sample: 500/mo, 7% for 30y (end)
Assumes a constant annual growth rate with monthly compounding: r = (1+APR)1/12 − 1.