Investor Score
Also called Airbnb Investor Score, investment grade, letter grade. Last reviewed Oct 21, 2026 by Jeremy Werden
The Investor Score is BNBCalc's letter grade for a property, from A+ to F, built from its cap rate and cash-on-cash return. On the Short Term Rental card, cash on cash carries 85% of the weight, so the grade mostly tells you how hard the cash you'd put in would work.
Short-term rental score = 15% × (cap rate × 7.692) + 85% × (cash on cash × 5), rounded down, with both rates in percent (8% = 8)
How does BNBCalc grade a property?
Buy and Own analyses open with two cards, Short Term Rental and Long Term Rental, each with a letter grade. The short-term score is 15% × (cap rate × 7.692) + 85% × (cash on cash × 5), rounded down, and the grade follows from the score:
| Short-term score | Grade |
|---|---|
| 100 or more | A+ |
| 75 to 99 | A |
| 50 to 74 | B |
| 35 to 49 | C |
| 20 to 34 | D |
| Under 20 | F |
Neither part of the score has a ceiling, so a strong cash-on-cash return can carry the grade on its own: at 24%, a home reaches an A+ whatever its cap rate. And because the score is rounded down, a 20% cash-on-cash return with a 13% cap rate scores 99, an A, one point short.
Take a home with an 8.06% cap rate and a 7.00% cash-on-cash return. It scores 15% × (8.06 × 7.692) + 85% × (7.00 × 5) = 39, a C. Because cash on cash carries most of the weight, raising it by two points would lift the score by about 8, while the same rise in cap rate would add only about 2.
How is the Long Term Rental grade different?
The Long Term Rental card runs the same home as a 12-month lease with its own math: 30% × (cap rate × 12.5) + 70% × (cash on cash × 8.333), with A+ at 100, A at 85, B at 67, C at 55 and D at 44. Click the card to switch the page to the long-term view. Since the weights and bands differ, a C on one card and a C on the other don't mean the same thing.
What doesn't the Investor Score tell you?
The grade is only as good as the numbers behind it, so make sure your loan terms, price and expenses are real before you lean on it. It also leaves out everything that isn't a return, like the market's rules for short-term rentals, how seasonal the bookings are and how much work the home will take. Read it as a quick summary of the returns, then look at the cash flow and the Seasonality chart before you decide.