Dollar-Cost Averaging
Dollar-cost averaging is investing a fixed amount on a regular schedule regardless of price. You automatically buy more shares when prices are low and fewer when they're high, and — more importantly — you remove the timing decisions that most investors get wrong.
Every 401(k) contribution is dollar-cost averaging, which is why most people already do it without deciding to. The honest framing for a windfall is different from the marketing: historically, investing a lump sum immediately has beaten spreading it out roughly two-thirds of the time, simply because markets rise more often than they fall, so averaging in usually costs a little expected return. What it buys instead is regret insurance — the protection against putting everything in the week before a fall, which is the scenario that makes people abandon investing altogether. That trade is reasonable and worth naming as a trade. For ongoing contributions from income the question does not arise: you invest as you earn.
Put it to work
Investment Calculator
Project an investment portfolio's growth with monthly contributions — final value, your money vs market growth, and the year-by-year path.
Compound Interest Calculator
See how your savings grow with compound interest and monthly contributions — final balance, interest earned, and a year-by-year growth table.