Latte factor calculator

What the number means

The result is a thought experiment: what you would have if the money spent on a small habit had been invested at a steady return. The return is your assumption; real investments rise and fall, and some years lose money. The page shows three things next to each other, what you put in, what it could grow to and what that sum would buy in today's prices, so that the effect of time and of inflation can be seen separately from the effect of the habit itself.

The method

Yearly spend = amount × times per week × 52. Monthly deposit = yearly spend ÷ 12. With the yearly return r (in %), i = r ÷ 100 ÷ 12 and n months, the future value is deposit × ((1 + i)^n − 1) ÷ i; at r = 0 it is deposit × n. Value in today's money = future value ÷ (1 + inflation)^(n ÷ 12). Deposits happen at the end of each month. It is the same method as the future value and savings goal calculators.

Worked example

$5 on five days a week is $1,300 a year, $108.33 a month. After 30 years you have put in $39,000. At an assumed 6% a year the deposits grow to $108,822, of which $69,822 is growth. Divided by 1.03 to the power 30 (3% inflation), that is about $44,833 in today's money, which is $63,989 less on paper than the nominal total. The figures come from the same function as the calculator.

Limits of this method

The result is only as reliable as the assumed return. A constant 6% or 11% a year is not what markets deliver year by year, and the order of good and bad years matters. Taxes, fund fees and any employer match are left out. The method also assumes you would really have invested the money; many people would have spent it on something else, or should have used it to pay off debt with a higher interest rate than any investment return. And the idea has been criticized for putting the weight of a financial plan on small daily purchases, when housing, transport and income usually matter much more.

What is the latte factor?

It is the idea that a small daily purchase, such as a coffee, adds up to a large sum over a lifetime if you invest the money instead. The phrase is credited to the financial author David Bach. According to a retrospective in The Hustle, he first used 'The Latte Factor' in 1995, as shown by a trademark he later filed, and presented it in his 1999 book Smart Women Finish Rich, starting from a woman in one of his classes who bought a latte every day and never had money to invest. He later widened the idea to other small regular costs. We have not read the book; these details come from that article, so treat them as reported, not verified from the original.

How much would a daily $5 habit be worth if invested?

It depends on the return, and the return is a guess. With example values, not a forecast: $5 five days a week is $1,300 a year, or $108.33 a month. Invested for 30 years at an assumed 6% a year it grows to $108,822, of which $39,000 is money you put in. At 3% the same habit reaches $63,130; at 0% it is just $39,000. With 3% inflation the 6% result is about $44,833 in today's money. The spread between those outcomes is the point: the answer is only as good as the return you assume.

Are the famous latte factor numbers realistic?

Published accounts of the original claim differ, and critics say the arithmetic was too generous. One account says Bach claimed $5 a day at 11% would pass $2 million by age 65; another says more than $1 million at a 10% to 11% return. We cannot confirm either figure from the book. Our own arithmetic, with the same formula as the calculator, for $5 seven days a week over 40 years at 11% a year gives $1,304,353, with $72,800 contributed; at 7% it gives $398,097. A long-run return of 11% is also higher than many people would plan on, and it is never guaranteed.

What do critics say about the latte factor?

Several points are reported. Journalist Helaine Olen, in her book Pound Foolish, argued that the claim did not hold up; Cliff Robb of the University of Wisconsin–Madison objected to making people feel guilty about small purchases while safety nets have weakened; and a 2012 dissertation by Jeffrey Lundy found that above-average discretionary spending usually did not explain differences in net wealth, while events such as divorce, job loss, high-interest debt, major health costs and widowhood did (all as summarized by The Hustle; we have not read the originals). Defenders reply that the point is to look at small regular costs, not to ban coffee, and a financial planner quoted in the same article calls it an entry point rather than a plan.

How does the calculator work out the future value?

It treats the spending as a monthly deposit: amount × times per week × 52 ÷ 12. Each deposit is made at the end of the month and the yearly return is divided by 12, so the future value is deposit × ((1 + i)^n − 1) ÷ i, with i the monthly rate and n the number of months. At a zero return it is just deposit × months. The value in today's money is the future value divided by (1 + inflation)^years. This is the same method as the savings goal and future value calculators; the 52 weeks and the monthly steps are simplifications.

Should I stop buying coffee?

The calculator does not say. It prices one choice so that you can decide with the number in view. For some people a coffee is a small pleasure that makes a day better; for others a daily purchase has become unnoticed. Large items usually matter more than small ones: housing, transport and food, together with income, set most of a budget. The budget calculator is a better place to see where the biggest amounts go. If you do redirect the money, make sure it goes somewhere that fits your situation, such as paying down high-interest debt, or an emergency fund first.

Why does the result change so much with the years?

Growth builds on earlier growth, so most of the gain comes late. In the example, 10 years of the habit grows to $17,754, 20 years to $50,054 and 30 years to $108,822. The table in the result shows the steps. A negative return is allowed in the form, because markets can fall; in that case the future value is below what you put in.

An estimate for planning only — not tax or investment advice; investments can lose value and no return is guaranteed. Sources, checked October 28, 2026 (secondary; the book and the dissertation were not opened): The Hustle, thehustle.co/originals/just-stop-buying-lattes-the-origins-of-a-millennial-housing-myth (origin of the phrase, Bach's claim, and the critiques by Helaine Olen, Cliff Robb and Jeffrey Lundy). David Bach, Smart Women Finish Rich (1999). The future value formula is the standard annuity formula. Related: the compound interest calculator, future value calculator, savings goal calculator, budget calculator and subscription cost calculator. How we check our calculators.