The gross rent multiplier (GRM) is a fast property-screening ratio: purchase price divided by gross annual rent. It tells you roughly how many years of gross rent it would take to cover the price, so investors use it to shortlist rental properties before running a full analysis.
How it works
The calculator applies one formula:
GRM = property price ÷ gross annual rent
“Gross” means total rental income before any expenses such as taxes, insurance, maintenance or vacancy. A lower GRM means the property costs fewer years of rent to pay for, which is generally more attractive. You can also rearrange it to estimate value: price ≈ GRM × gross annual rent.
Example
A property is listed at $240,000 and rents for $2,000 per month:
- gross annual rent = 2,000 × 12 = $24,000
- GRM = 240,000 ÷ 24,000 = 10.0
A comparable unit at the same $24,000 rent but priced at $200,000 has a GRM of 8.3 — the lower multiplier flags it as the better-value option to investigate.
| Price | Gross annual rent | GRM |
|---|---|---|
| $200,000 | $24,000 | 8.3 |
| $240,000 | $24,000 | 10.0 |
| $300,000 | $24,000 | 12.5 |
Using GRM as a screening tool
GRM is most useful as a fast first filter across a batch of listings, not as the final metric for a buying decision. Here is how to use it properly:
Calculate a local benchmark first. Before applying GRM to a prospect, survey three to five recently sold comparables in the same submarket and calculate their GRMs. If the local norm is around 9 and a listing shows 13, you know immediately that it is priced high relative to its income without running any deeper analysis.
GRM assumes comparable expense ratios. The multiplier ignores operating costs entirely. Two properties in the same neighbourhood with the same GRM can have very different net returns if one has aging HVAC and a flat roof while the other is recently refurbished. Once GRM narrows your list, always move to a cap rate or pro-forma net operating income analysis.
Estimate value from GRM. If you know that similar buildings sell at a GRM of 9, and a property grosses $30,000 per year, an indicative value is 9 × $30,000 = $270,000. This reverse calculation is common in informal appraisals.
GRM ignores vacancy. Gross rent is the scheduled rent at full occupancy. A property with chronic vacancy effectively has a lower true GRM than the headline figure suggests. Ask for actual collected rent, not market rent, before finalising the ratio.
GRM ignores expenses, so pair it with cap rate or cash-on-cash return before deciding. All calculations stay in your browser.