What Is MER? Formula, Meaning, and MER vs. ROAS
MER compares total store revenue with total marketing spend, helping readers calculate the ratio and distinguish its storewide view from campaign-level ROAS.
Marketing efficiency ratio (MER) is total store revenue divided by total marketing spend across all channels. It's also called media efficiency ratio. MER shows how much revenue the store earns for each marketing dollar. It doesn't identify the campaign or channel that produced it.
How MER is calculated
Use total store revenue and all marketing costs from the same dates. Revenue includes paid, organic, and unattributed sales because MER measures the whole business.
Add every marketing cost from:
- Paid ad spend from every platform
- Influencer and affiliate fees tied to promotion
- Production costs for ads and campaigns
- Marketing software, agency, and contractor costs
Product cost, shipping, payment fees, and overhead stay out of this calculation. They matter to profit, but they aren't marketing expenses. Use the same dates for both inputs. Costs paid outside ad platforms still belong in the spend total.
Suppose your store earns $200,000 and spends $50,000 on marketing in one month. The result is a MER of 4. The store earned $4 in revenue for each $1 spent on marketing.
Why MER matters
MER shows whether your total marketing budget is efficient across the business. That view matters when customers see an ad on one platform, search later, and buy through another source. A platform dashboard may claim the sale, while the blended figure captures the combined effect without trying to assign credit.
Check each channel too because strong channels can hide a losing campaign. Customer acquisition cost answers another part of the decision. Calculate it from campaign spend and conversions with our CPA calculator.
MER vs. ROAS
MER measures revenue against marketing spend for the whole business, while return on ad spend (ROAS) measures one campaign or channel. Northbeam's comparison supports this scope split. A store may have several ROAS figures but only one MER for the matching period.
Use MER to judge the combined budget and ROAS to compare campaign results. You can use our ROAS calculator for the channel figure.
Neither metric proves that the store is profitable. Both leave out other costs, which contribution margin brings into the decision.
FAQ
These answers cover MER benchmarks and common calculation problems.
What's a good MER for a dropshipping store?
Shopify places a healthy MER around 3.0x-5.0x, while Northbeam says 5.0x or higher can be good. Those ranges aren't universal because margins, growth stage, industry, and acquisition costs change the result a store needs.
Can I calculate MER without an agency?
Yes, you can calculate MER without an agency. A spreadsheet is enough if revenue and marketing costs cover the same dates and the spend total includes every channel.
Why can ROAS look fine while MER looks bad?
ROAS can look fine while MER looks bad when channel reports omit costs or claim overlapping revenue. Creative, influencer, agency, and software expenses can weaken the storewide result even when each ad dashboard reports an acceptable return.
