What Is the Absorption Rate?
The absorption rate measures how quickly homes are selling in a given market. It is calculated by dividing the number of homes sold during a period by the number of active listings, giving the percentage of inventory absorbed per month. The closely related "months of inventory" figure tells you how long it would take to sell every current listing if no new homes came on the market.
How to Use This Calculator
Enter the number of active listings (current inventory), the number of homes sold, and the length of the sales period in months. The calculator converts sales into a monthly pace, then computes the absorption rate and months of inventory. As a rule of thumb, fewer than about 5–6 months of inventory signals a seller's market, while more than 6–7 months points to a buyer's market.
The Formula Explained
First we find homes sold per month: Homes Sold ÷ Period. Months of Inventory is then Active Listings ÷ Homes Sold per Month. The absorption rate as a percentage is (Homes Sold per Month ÷ Active Listings) × 100. The two metrics are reciprocals scaled to different units.
Worked Example
Suppose a market has 200 active listings and 60 homes sold over 3 months. Homes sold per month = 60 ÷ 3 = 20. Months of inventory = 200 ÷ 20 = 10 months. Absorption rate = (20 ÷ 200) × 100 = 10% per month. Ten months of inventory indicates a buyer's market with relatively slow sales.
Months of Inventory Market Thresholds
The absorption rate measures how quickly homes sell in a given market. Months of inventory (MOI) is its inverse — the number of months it would take to sell all current active listings at the current pace of sales. The two are directly related:
The widely used real-estate rule of thumb interprets these figures as follows. A high absorption rate (low inventory) favors sellers, while a low absorption rate (high inventory) favors buyers.
| Months of Inventory | Monthly Absorption Rate | Market Type | Implication |
|---|---|---|---|
| < 4 months | > 25% | Strong seller's market | Low supply, fast sales, rising prices, bidding wars likely |
| 4 – 6 months | 16.7% – 25% | Seller's market | Demand outpaces supply; favorable conditions for sellers |
| 6 – 7 months | 14.3% – 16.7% | Balanced market | Supply and demand roughly even; prices stable |
| > 7 months | < 14.3% | Buyer's market | Excess supply, slower sales, downward price pressure |
As a worked check, a market with 120 active listings and 30 homes sold over a 2-month period sells 15 homes per month, giving a monthly absorption rate of 12.5% — corresponding to 8 months of inventory, which falls in the buyer's-market range.
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