Future value calculator, solve for any number.

Future value is what money put away today, with deposits added along the way, grows to at a given rate. This future value calculator works out that number from a starting amount, a regular deposit, a yearly rate and a time. It also runs the sum backwards. Pick what you want to find, Future value, Start, Deposit, Rate or Time, and the page solves for it from the other four. A chart, a table by year and a CSV come with the answer. It claims no rates. The 6 percent in the box is an example, not a forecast.

How to use it

1. Under What are you working out pick the one thing you want to find.
2. Type the other numbers: Starting amount, Deposit each period, Yearly rate (%) and Years. When you solve for something other than the future value, also type the Amount you want to reach.
3. Pick how often Interest and deposits are added, and whether Deposits are made At the end or At the start of each period.
4. Read the big card, the chart and the table. Download table (CSV) saves the table and Copy link to these numbers reopens the page with your inputs.

The formula

With i as the rate for one period (the yearly rate divided by how many periods are in a year) and n as the number of periods, the future value is FV = PV x (1 + i)ⁿ + PMT x ((1 + i)ⁿ − 1) / i. If deposits are made at the start of each period, the deposit part is multiplied by (1 + i). With a rate of 0 it is simply PV + PMT x n. Solving for the start or the deposit is a rearrangement of the same line. Solving for the time uses a logarithm. Solving for the rate has no neat formula, so the page searches for it.

A worked example

Start with 10,000, add 200 a month for 10 years at a 6 percent yearly rate, interest added monthly. There are 120 periods and i is 0.5 percent. The future value is 50,969.84. You put in 34,000 (10,000 plus 120 deposits of 200), so the interest is 16,969.84. If each deposit goes in at the start of the month, the future value is 51,133.72, which is 163.88 more because every deposit earns one more month.

Working backwards

Say you want 50,000 in 10 years with the same 6 percent and monthly deposits. If you already have 10,000, you need to deposit 194.08 a month. If you deposit 200 a month, you only need 9,466.95 to start. If you have 10,000 and deposit 200 a month, the rate needed to reach 50,000 in 10 years is 5.7267 percent, and at 6 percent the goal arrives after 9 years and 10 months.

Lump sums and how often interest is added

With no deposits, 10,000 at 6 percent added yearly becomes 17,908.48 after 10 years. A lump sum of 5,000 at 5 percent, added quarterly, becomes 13,507.42 after 20 years. Adding interest more often gives slightly more, but the rate matters far more than the schedule. For the other side of this, the APY calculator converts a stated rate into the yield you really get.

Checks and common mistakes

The most common slip is mixing the yearly and the period rate. A 6 percent yearly rate added monthly is 0.5 percent a month, and 10 years is 120 periods. The page does that conversion for you from the schedule you pick. Another slip is comparing deposits made at different times. Saving 200 a month for 10 years at 6 percent, added monthly, reaches 32,775.87. Saving 2,400 once a year with yearly interest reaches 31,633.91, because the money goes in later. Deposits at the start of each month reach 32,939.75.

A quick check is to run the numbers with a rate of 0. The future value is then the start plus the deposits, 10,000 + 24,000 = 34,000 here, and every extra above that is interest. If your result is below that, something is wrong with an input.

What the page leaves out

• Tax, fees and inflation. Money will buy less in the future. See the inflation calculator.
• Rates that change. The page holds one rate for the whole time.
• Deposits that differ from the interest schedule, or that grow each year. For raises and today’s money use the compound interest calculator.