Milestone speed calculator
Not the balance over time — the time each identical step takes. It shrinks, and the reason it shrinks is the whole of compounding.
Time to cross each $100,000
Each bar is the time that step alone took — not the total.
The first $100,000 takes 6y 8m. The step up to $1,000,000 takes 1y 3m — about 5.3× faster, with the same contribution and the same return.
Nothing changed except the size of the balance doing the earning.
How much of each milestone you actually paid for
| Balance | You contributed | Growth | Growth share |
|---|---|---|---|
| $100,000 | $80,000 | $20,000 | 20% |
| $200,000 | $133,000 | $67,000 | 34% |
| $300,000 | $174,000 | $126,000 | 42% |
| $400,000 | $207,000 | $193,000 | 48% |
| $500,000 | $235,000 | $265,000 | 53% |
| $600,000 | $259,000 | $341,000 | 57% |
A steady return stands in for real markets, which deliver returns in a lumpy order — so treat the pattern as the point rather than the dates. It also ignores inflation, taxes, and fees, and assumes the contribution never changes, while most people’s rises over a career.
Why each step is faster than the last
Reaching the first milestone is almost entirely your own money. There is barely any balance, so returns have almost nothing to work on — you are effectively saving your way there.
By the fifth milestone the balance is large, and its returns are doing a meaningful share of the lifting. By the tenth, growth supplies most of each step and your contribution is topping it up.
Nothing about you changed. You did not start earning more or investing better. The only thing that changed is the size of the balance doing the earning.
The same fact, from a more useful angle
A normal compounding chart shows a curve rising, which is true and not very motivating — the interesting part is thirty years away.
Measuring time-per-milestone puts the same arithmetic on a scale you actually live on. It answers “how long until the next one?” rather than “what will this be worth in 2056?”, and the answer keeps improving.
It is the same effect described in why compounding is back-loaded, read from the side that feels less discouraging.
What the table underneath shows
At the first milestone, most of the balance is money you put in. Several milestones later, growth has overtaken contributions — and that crossover is the point where the account starts doing more work than you do.
Watching that percentage climb is a better progress measure than the balance itself, because it tells you how much of the machine is running on its own.
What this ignores
A steady return, which no market delivers — real markets arrive lumpy, so a real milestone can take much longer or much less than the schedule here. It also ignores inflation, taxes and fees, and assumes a contribution that never changes, while most careers raise it.
The pattern is the point, not the dates.
Related: why the first $100,000 is the slowest · compound growth calculator
Educational only. This explains how these products and accounts work in general. It is not financial, tax, or legal advice, and not a recommendation to buy anything. Your situation is specific to you — check with a licensed professional before acting.