The opposite of the Degen-Trade Calculator on purpose. No leverage, no lotto tickets, just what happens when you put money in consistently and let time do the actual work. This is the boring way that works.
Not financial advice. This assumes a constant annual return, which real markets never actually deliver. Real returns are lumpy and unpredictable year to year, even if they average out over long periods. Past performance is not indicative of future results. Consult a licensed financial advisor before making any investment decision.
Why compounding is the whole game
Compound growth means you earn returns on your original money and on the returns it already made. Early on it looks slow. Given enough years, the gap between what you put in and what you end up with stops looking real. That gap is compounding, working quietly in the background the entire time.
Change any number below and everything updates live: the chart, a year by year table, a goal solver, a simulation of bumpy real-world returns, and the cost of waiting, fees and stopping early. Hover over the charts to read exact numbers.
Compound Growth
Money in each month, a steady yearly return, and time. No leverage and no lottery tickets.
What you put in on day one
What you add each month after that
8 is a rough long-run stock market average, not a promise
How long you leave it alone
0 keeps it flat. 3 means you add 3% more each year
Used to show what the money buys in today dollars
What You End With (Final Balance)
$0
At the end of your years
What You Put In (Total Contributed)
$0
Start amount plus every month
What Compounding Added (Growth)
$0
Free money from returns on returns
Growth Multiple
0.0x
Final balance over what you put in
Buying Power In Today Dollars (Real Value)
$0
After inflation
Possible Monthly Income (4% Rule)
$0
Taking 4% of the balance a year
Growth Earned In The Final Year
$0
Versus what you added that year
Year Growth Beats Your Savings (Crossover)
-
When returns out-earn deposits
Share Of The End From Growth
0%
The rest is money you put in
Money Doubles Every (Rule Of 72)
-
Years, with no new deposits
Reach A Goal
Pick a target and see how long it takes, how much you would need to add each month, or what yearly return you would need.
The balance you want to reach
Today dollars adjusts for rising prices, the honest choice for long goals
Your Goal At The End (Future Dollars)
-
What you must have then
Where Your Plan Ends Up
-
With the numbers above
Ahead Or Behind The Goal
-
Plan end minus goal
Years To Reach It (Your Plan)
-
At your monthly amount and return
Monthly Amount Needed (Your Years)
-
To reach it in the years above
Yearly Return Needed (Your Plan)
-
With your monthly amount and years
In plain English: there are only three levers: how much you add, how long you wait and what return you earn. Each card changes one lever and holds the other two where you set them. Time is the one that costs nothing, and the return is the one you control least, so be careful about solving a goal by assuming a high return.
Real Markets Are Lumpy
The calculator above grows at the same rate every year. Real markets do not. This simulation runs 400 possible futures where each year the return swings up or down around your average.
15 is close to the stock market. 0 means a perfectly smooth ride
Smooth Plan (Constant Return)
-
The number from the top of the page
Typical Future (Median)
-
Half of futures finish above this
Unlucky Future (10th Percentile)
-
1 future in 10 finishes this low or lower
Lucky Future (90th Percentile)
-
1 future in 10 finishes this high or higher
Chance You End Below What You Put In
-
Finishing with less than your deposits
Chance You Reach Your Goal
-
Using the goal from the section above
The Cost of Waiting
Same monthly amount, same rate. The only difference is when you start. This is the single most expensive decision in investing, and it is usually made by accident.
How many years you put it off
Start Today
$0
Wait, Then Start
$0
If You Wait
Final Balance
You Lose Versus Starting Today
Share Lost
The Cost of Fees
A 1% annual fee sounds tiny. Over decades, compounded against you instead of for you, it is not.
What your fund or advisor charges each year
No Fee
$0
With Fee
$0
Yearly Fee
Final Balance
Lost To Fees
Share Lost
What Happens If You Stop
Life happens. This shows what your money keeps doing even if you have to stop adding to it partway through.
Year you stop adding money
Keep Adding The Whole Time
$0
Stop Early, Let It Ride
$0
Stop Adding After
You Put In
Final Balance
Share Of The Full Plan
Visualizer
Your plan drawn to scale, then the year by year table and the final balance maps. Everything here updates from the inputs above.
Growth over time
What you put inBalance with compoundingBalance in today dollars
Move your cursor over the chart to read the balance in any year.
In plain English: notice how flat the growth looks for the first several years, then how sharply it bends upward. That is how compounding behaves, not a quirk of this calculator. Most people quit right before the curve gets interesting. Rule of 72: at 8% a year your money roughly doubles every 9 years, with no contributions needed, just time and that rate holding steady. The dashed line is the same balance after prices rise, because a dollar in 20 years buys less than a dollar today.
Real markets are lumpy (simulation)
Typical future (median)Smooth planMiddle 80% of futures
Move your cursor over the chart to read the range of balances in any year.
In plain English: the shaded band holds eight out of ten simulated futures. Even with the same average return, the path matters: a bad stretch early costs more than the same bad stretch late, because you have less money invested to lose but also less time to recover. Ups and downs also pull the typical result a little below the smooth line. The plan is not broken when the market dips, it is working through a range like this one.
Year By Year
Where your balance stands at the end of each year, and how much of the year came from your deposits and how much from growth.
Year
Balance At Start
You Added
Growth Earned
Balance At End
In Today Dollars
In plain English: watch the growth column. In the early years your deposits do most of the work. Later, the growth column passes your deposits and keeps climbing, even if you add exactly the same amount. That is the point where the money starts working harder than you do.
Final Balance Maps
How your final balance changes when you change the return, the years or the monthly amount. Your own numbers are outlined in gold.
Yearly return against years
Yearly return against monthly amount
In plain English: read across a row to see what adding more time or more money does, and down a column to see what a different return does. Notice that more years usually beats a higher return, and that adding a bit more each month often matters more than chasing a point or two of extra growth.