Nummira

Savings calculator

How long until your goal — and what gets you there faster.

Runs entirely in your browser. We don't send or store what you type.

7.0%

You'll reach 100,000 in 10 years 4 months 13 days

around February 2037

26.7K53.3K80K2026202820302032203420362037
BalanceInvested

Projections use a fixed average return (optionally inflation-adjusted) and assume steady contributions. Real markets are volatile; taxes and fees are not included. Educational only, not financial advice.

Continue in the app

Nummira runs this math live on your real portfolio — no spreadsheets to update.

Continue in the app

Starting with $5,000 and saving $500 a month at a 7% annual return, you reach $100,000 in about 10 years and 5 months. Change the numbers above — the result updates instantly.

How compound interest is calculated

We convert the annual return to an effective monthly rate — (1 + r)^(1/12) − 1 — and compound your balance every month while adding your contribution. Time-to-goal uses the annuity formula n = ln((F·i + C) / (P·i + C)) / ln(1 + i), where P is your start, C the monthly contribution, F the target and i the monthly rate.

Why starting early beats a higher return

Compounding rewards time more than rate. $200 a month at 5% for 30 years grows to about $163,000 — while $400 a month at 5% for 15 years reaches only about $106,000, despite double the saving rate. The years you don't wait are the cheapest capital you'll ever get.

Example: from $100 to $100k

Starting with $100 and saving $500/month: at 0% you need about 16 years 8 months; at 3% about 13 years 7 months; at 5% about 12 years 3 months; at 7% about 11 years 2 months. The year-by-year table under your results shows the path for your own inputs.

Saving for freedom rather than a number? Compute it through the FIRE calculator.

Calculator FAQ

Is interest compounded monthly or yearly?
You enter an annual return; we convert it to the equivalent monthly rate ((1+r)^(1/12) − 1) and compound monthly, which matches how regular contributions actually accrue.
What does the inflation toggle do?
It switches the math to a real (inflation-adjusted) return: (1 + return) / (1 + inflation) − 1. Your goal then means "this amount in today's purchasing power", and the horizon typically gets longer.
Why is the date approximate?
The model assumes a perfectly steady return and contributions on an exact monthly rhythm. Real markets wobble around the average, so read the date as a midpoint, not a promise.
Can the goal be unreachable?
Yes: with no contributions and no return, or when a negative real return shrinks your balance faster than you add to it. The calculator says so explicitly instead of showing a fake date.
Is my data stored anywhere?
No. Everything is computed locally in your browser. Inputs only leave your device if you copy the share link yourself.