Savings Growth Calculator

See how contributions and a chosen rate affect a savings projection.

See your contributions and a constant-rate growth scenario together.

Updates as you type

Results

Your numbers

Start with the example. Change it to fit your plan.

Starting amount

Monthly deposit

Time to grow

Annual rate

An illustrative constant rate, not a forecast. Values in percent.

How the rate is quoted

APY already includes compounding. A nominal rate does not.

Monthly deposit arrives

Nominal annual rate divided by 12. Interest credited monthly to the cent; deposits at month start. Excludes taxes, fees, withdrawals, inflation and changing rates. Returns are not guaranteed.

Your result

Projected balance after 10 years$15,519.50

$500 to start, then $100 a month at an illustrative 4% nominal rate for 10 years.

Your contributions · $12,500 Projected growth · $3,019.50

Your contributions$12,500

Projected interest / growth$3,019.50

Where the balance comes from

Projected balance
Your contributions
+$50 per month

The lines use the same monthly projection as your results. Intermediate months are sampled; the final point is exact for this model.

View chart values

Plotted points; intermediate months are sampled on longer timelines.
Time	Projected balance	Your contributions	+$50 per month
0 yr	$500	$500	$500
0 yr 5 mo	$1,013.41	$1,000	$1,265.92
0 yr 10 mo	$1,535.43	$1,500	$2,044.69
1 yr 3 mo	$2,066.21	$2,000	$2,836.53
1 yr 8 mo	$2,605.91	$2,500	$3,641.66
2 yr 1 mo	$3,154.65	$3,000	$4,460.29
2 yr 6 mo	$3,712.60	$3,500	$5,292.66
2 yr 11 mo	$4,279.91	$4,000	$6,139
3 yr 4 mo	$4,856.74	$4,500	$6,999.52
3 yr 9 mo	$5,443.24	$5,000	$7,874.49
4 yr 2 mo	$6,039.60	$5,500	$8,764.15
4 yr 7 mo	$6,645.96	$6,000	$9,668.72
5 yr	$7,262.49	$6,500	$10,588.48
5 yr 5 mo	$7,889.36	$7,000	$11,523.66
5 yr 10 mo	$8,526.75	$7,500	$12,474.53
6 yr 3 mo	$9,174.85	$8,000	$13,441.36
6 yr 8 mo	$9,833.81	$8,500	$14,424.41
7 yr 1 mo	$10,503.83	$9,000	$15,423.95
7 yr 6 mo	$11,185.09	$9,500	$16,440.27
7 yr 11 mo	$11,877.79	$10,000	$17,473.64
8 yr 4 mo	$12,582.10	$10,500	$18,524.35
8 yr 9 mo	$13,298.22	$11,000	$19,592.70
9 yr 2 mo	$14,026.36	$11,500	$20,678.96
9 yr 7 mo	$14,766.72	$12,000	$21,783.45
10 yr	$15,519.50	$12,500	$22,906.47

What if you added $50 a month?

Projected balance$22,906.47

Difference after the same timeline$7,386.97

This includes $6,000 more contributions, plus projected growth.

Keep a copy of your plan

Open in Google Sheets

Excel and PDF use the numbers above. Google Sheets opens a separate example in your Drive; to bring your own numbers, import the downloaded Excel file.

Saved only in this browser.

First deposit or payment date

Choose the first date. Reminders follow the deposit or payment schedule above, with the last amount adjusted when needed. No calendar account is connected.

Files are created in this browser. Financial inputs are not sent to our server.

Results are educational estimates from your inputs and the assumptions shown, rather than a guarantee or individual financial advice. About our estimates.

Savings Growth Calculator — filled public example — Filled public example. Your own entries are never shared.

Make this plan work for you

Project how a starting balance, monthly deposits, and a chosen rate grow over time. The filled example shows a ten-year plan at a nominal annual rate.

Enter your starting amount, monthly deposit, years, annual rate, and rate convention.
Set deposit timing to beginning or end to match when you actually add money.
Change the inputs and watch the calculated results update.

A filled example

Example inputs: Starting amount: $500.00; Monthly deposit: $100.00; Years: 10; Annual rate: 4%; Rate convention: nominal; Deposit timing: beginning

Plan	Result
Projected balance	$15,519.50
Your contributions	$12,500.00
Projected growth	$3,019.50

These results use the example inputs shown above. Change the inputs in the calculator to explore your own plan.

Adjusting inputs and choosing a format

Raise the deposit, extend the years, or test different rate conventions to see which change moves the projection most. Constant rates are scenarios, so testing several values shows how sensitive the result is to your assumptions. The calculator runs entirely in your browser and no financial inputs are uploaded. You can download the current inputs as an Excel file or PDF, or open a Google Sheets copy of the master example, which requires a Google account and contains the example rather than your browser inputs. No account is required to use the calculator itself.

Reading the ten-year example

The filled example uses a $500 starting amount, a $100 monthly deposit, ten years, a 4% nominal annual rate, and beginning-of-month deposits. Comparing Projected growth with Your contributions shows how much of Projected balance comes from interest rather than deposits over the decade. If growth looks small relative to contributions, compare different timelines and assumed rates to see how each changes the projected result.

Frequently asked questions

Does the savings growth calculator save my inputs?

No. The calculator runs in your browser and no financial inputs are uploaded. If you want a saved copy, download the Excel or PDF version, which contains your current inputs.

What does deposit timing change?

Beginning timing deposits each amount at the start of the period so it earns interest sooner; end timing deposits it later. The convention matches the website, so pick whichever reflects when you actually add money each month.

Is the projected balance a guaranteed result?

No. The projection uses a constant rate you choose, which is a scenario rather than a forecast. Actual account rates can change, so rerun the calculator with several rates to see a range of possible outcomes.