Investment growth calculator
Project a starting amount plus regular contributions, using honest historical averages, and see the result in today's dollars.
View yearly schedule
Projections are illustrations based on your inputs, not predictions or advice. Actual returns vary year to year.
Why steady contributions matter more than timing
Most wealth built in markets comes from two unglamorous habits: contributing regularly and staying invested. Contributing on a schedule, sometimes called dollar cost averaging, means you automatically buy more shares when prices are low and fewer when they are high, and it removes the temptation to guess the right moment.
Our presets reflect long run historical averages, not promises. US stocks have averaged roughly 10% a year nominal over the last century, but with brutal interruptions: drops of 30% to 50% happen and recoveries take years. The conservative 7% default acknowledges that the next decades may be leaner than the last.
The inflation adjusted figure matters most. A million dollars in 30 years buys far less than a million today, so plan in today's dollars. See what markets actually return for sources and caveats behind these presets.
Common questions
What return should I assume for the S&P 500?
The long run historical average is close to 10% a year before inflation, or about 7% after inflation. Many planners use 6% to 8% nominal to stay conservative, since future returns are unknown.
Should I invest a lump sum or spread it out?
Historically a lump sum invested immediately has beaten gradual investing about two thirds of the time, because markets rise more often than they fall. Spreading it out reduces regret if a crash follows. Both are reasonable.
Does this account for taxes and fees?
No. Use your net expected return, after fund fees, and remember taxable accounts owe tax on dividends and realized gains. Our fee impact calculator shows how much fees change the outcome.