Amazon’s Best Seller Rank (BSR) indicates how a product is selling compared to other products in its category. A strong BSR tells Amazon’s search algorithm that a product is trending upwards and should be optimized in search results.
But what is your BSR and how do you calculate it?
Amazon has not released how BSR is exactly calculated. In Amazon's description of BSR, they write: “The Amazon Best Sellers calculation is based on Amazon.com sales and is updated hourly to reflect recent and historical sales of every item sold on Amazon.”
This isn’t very specific.
Below, we go into popular opinions and our own experience to get into the details of BSR calculation… and if it even matters.
What is BSR?
The Best Sellers Rank or Sales Rank is an indicator of both a product’s recent sales and its historical sales volume in comparison to other products in a given category.
On a product listing, you’ll see the Best Seller Rank under “Product Details.” This will show that product’s rank within its overall category as well as applicable subcategories. For example, a waffle maker might be #6,410 in Kitchen & Dining but #30 in Waffle Irons specifically.
Pro-Tip: If a product doesn’t have a BSR, it’s likely a new unit without any sales.
What is the purpose of BSR?
A higher product sales rank or BSR may help the product listing move towards the top of Amazon’s search results.It can also give you more visibility, as Amazon’s algorithm naturally promotes bestselling products under the “customers who also bought” section.
Ultimately, though, the most important part of Amazon Sales Rank is the Best Sellers list. Those products in the top sales rank for their categories are displayed on the prime real estate of Amazon’s “Best Seller” list.
How is BSR calculated?
BSR is calculated hourly based on three key factors: category, recency (how recently the product was sold), and sales.
The BSR ranks products in comparison to one another in the same category. Thus, a product can have different ranks in different markets.
Amazon’s algorithm seems to care most about the top-level category. This means it’s more likely to favor higher-ranking products in department categories like “Home & Kitchen.” If a customer goes to Amazon’s search bar and types in a key phrase, the algorithm will consider the BSR for the appropriate department as opposed to specific categories.
However, if a customer is searching within a specific sub-category, Amazon’s algorithm likely looks at the BSR ranking for that particular category. For example, a customer filters their search to look specifically in the “Home & Kitchen” subcategory “Vacuums & Floor Care.” Amazon’s algorithm will then take into account the BSR of the sub-category because it will prove more relevant to the customer’s search.
Recommended Reading: How To Obtain Approval To Sell In Restricted Categories
BSR is not the best selling product of all time. The #1 BSR right now means it’s the best selling product in that category recently.
The BSR takes time frame into account. The BSR updates every hour, and the algorithm more heavily weighs a recent volume of sales over the cumulative number of sales.
If a waffle iron had 10 new sales in the last hour and a vacuum filter had 20 new sales, the vacuum filter with 20 sales will likely have a higher BSR. If, in the next hour, the waffle iron has 20 new sales and the vacuum filter has 5 new sales, the waffle iron may be able to knock into a higher ranking over the filter.
Best Seller Rank updates hourly, taking the sales of the last hour and day heavily into account.
Because the BSR is based on recency, it’s a poor indicator of past or cumulative sales. The BSR can fluctuate drastically every week, day, or even hour because it looks at sales in the recent past.
However, most experts believe that the total volume of sales also plays some role. You still need to sell more units than others in that category to gain the number one spot.
For example, a waffle iron is at BSR #20 and a vacuum filter is BSR #10. Over the past quarter, the waffle iron has had 100 sales and the vacuum filter has had 1,000 units sold. In the last hour, the waffle iron sold 20 units and the vacuum filter sold 1.
Even though the waffle iron sold more units in the past hour, the vacuum filter still has so much more volume over time that it likely wouldn’t move much in BSR ranking. The waffle iron may move to spot BSR #11, but those 20 recent sales may still not be able to compete with the historical 1,000 sales of the vacuum filter.
BSR may consider the total volume of sales because Amazon has a predictive analytics algorithm. Their algorithm will look at historical and recent sales data to determine whether the product is trending up or down. Products on the upswing usually have a higher BSR than those that are stagnant or slowing down.
Consider this. The waffle iron has only sold 100 total units. In the past day, the waffle iron has sold 1,000 units. This signals Amazon that the waffle iron is exploding in popularity, so it will boost the BSR.
The vacuum filter, though, has 1,100 total units sold in the past two months. In the past day, it has only sold 10 units. This tells Amazon that the vacuum filter is slowing down in popularity.
Even though both products have 1,100 units sold—it’s ultimately the recent quantity that tells Amazon whether or not the product is trending in the market.
Do reviews matter?
Some sellers mistakenly think that the Sales Rank takes into account reviews or ratings. It likely doesn’t.
BSR looks solely at sales data, both recently and historically. The BSR metric likely doesn’t account for rating average.
In fact, the product’s reviews are likely a more favorable metric in Amazon’s search algorithm than even BSR.
Check out The Merch Informer’s “Understanding Amazon BSR—5 Things You Need To Know Before Picking A Niche” for more great tips!
Is BSR important?
Not really. BSR is for vanity more so than optimization. Sellers get hung up on BSR because they want to feel like they’re the best. But unless you’re the #1 rank for your category, BSR doesn’t change your optimization or visibility all that much.
BSR is likely not a direct correlation with organic search results ranking.
Moreover, BSR can change drastically by the hour. It’s ineffective to get hung up on a number that fluctuates so constantly and has a number of uncontrollable variables.
What it comes down to: If you have quality products, optimized listing, strong marketing, positive reviews, and appropriate prices, you will convert more sales. If your product sells more, you’ll have a higher BSR.
Focusing on other aspects of product optimization is the key to improving your product’s standing, and ultimately, its best seller ranking.
Click to learn how to evaluate your Amazon strategy for 2018 based on controllable variables that will positively impact your BSR.
The Bottom Line
No one has the right answer for how to improve BSR. The rankings are constantly changing every hour, sometimes drastically. It’s also not a strong indicator of sales volume, as it only looks at product comparisons in a recent time frame.
Thus, ultimately, BSR doesn’t actually matter that much. Don’t waste your time thinking about your product’s Sales Rank, because it can and will change on an hourly basis.
Instead, focus on those variables you can and should control, like listing optimization and advertising.