See what a daily coffee or any small recurring habit costs per month and year, and a hypothetical future value if invested instead.
Latte Factor Formula
The calculator converts a repeated small purchase into a monthly cost, then projects what that money would become if invested:
M = C * A / 12; A = 365 daily, 260 weekdays, or 52*W custom purchases
FV = M * ((1 + r/12)^(12n) - 1) / (r/12)
Variables:
- M is the habit’s cost per month
- C is USD cost per purchase; A is annual purchases; W is the custom average purchases per week
- r is your assumed nominal annual return as a decimal; no return is prefilled or guaranteed
- n is the number of years (12n must be whole months); FV assumes equal month-end contributions and monthly compounding. At r = 0, FV = M × 12n
Enter the cost per purchase, schedule, period and assumed return, including zero or a negative return. The period and return are required. The calculator returns the weekly, monthly, and annual habit cost, the total spent over the period, the value if invested instead, and the compound growth on top of the spending – the “latte factor” itself.
Common Habits Invested for 10 Years at 7%
Illustrative projections using a 7% nominal annual rate compounded monthly and month-end contributions. Values exclude taxes, fees and inflation; they are not forecasts. Weekdays assume 260 purchases and daily schedules assume 365 per year.
| Habit | Monthly cost | Spent over 10 yrs | Hypothetical invested value |
|---|---|---|---|
| $5.50 latte, weekdays | $119.17 | $14,300.00 | $20,625.94 |
| $12 lunch out, weekdays | $260.00 | $31,200.00 | $45,002.05 |
| $18 delivery, 2x per week | $156.00 | $18,720.00 | $27,001.23 |
| $8 daily purchase | $243.33 | $29,200.00 | $42,117.30 |
| $4 energy drink, daily | $121.67 | $14,600.00 | $21,058.65 |
Example Problems
Example 1: The classic weekday latte.
A $5.50 latte on weekdays: W = 5, so M = 5.50 x 5 x 52 / 12 = $119.17 per month. Over 10 years that is $14,300 spent. Invested monthly at 7%: using the unrounded monthly contribution, FV = (1430/12) × [((1 + 0.07/12)^120 − 1)/(0.07/12)] ≈ $20,625.94.
Example 2: A twice-a-week delivery habit.
$18 per order, twice a week: M = 18 x 2 x 52 / 12 = $156 per month. Over 5 years at 7%, FV ≈ $11,168.49, versus $9,360 simply spent.
Frequently Asked Questions
What is the latte factor?
A term popularized by author David Bach for the long-term cost of small recurring purchases. The insight is not about coffee specifically – it is that any few-dollar habit, multiplied by hundreds of repetitions and compound growth, quietly represents five-figure money over a decade.
Does this mean I should never buy coffee?
No. The point is awareness, not deprivation: keep the habits that genuinely add to your life and consciously redirect the ones that do not. Redirecting savings can change your investment contributions, but actual outcomes depend on returns, costs, taxes and whether you invest the money.
What does the example 7% return mean?
The article uses 7% only as an illustrative nominal annual rate, divided by 12 for monthly compounding. The calculator requires your own assumption and makes no inflation adjustment. Actual investment returns vary and may be negative; no specific investment or rate is recommended.
