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Common Questions
Frequently Asked Questions
What is Marketing Efficiency Ratio (MER)?
Marketing Efficiency Ratio (MER) is the total revenue your business generates divided by total advertising spend across all channels. It is calculated as: MER = Total Revenue / Total Ad Spend. A MER of 4x means you generated $4 in revenue for every $1 spent on advertising. Unlike platform ROAS, MER looks at your entire business, not just one channel in isolation.
How is MER different from ROAS?
ROAS (Return on Ad Spend) is platform-specific and measures the revenue a single ad channel reports attributing to itself. MER is blended - it measures total business revenue against total ad spend across every channel. Because different platforms all claim credit for the same sales, platform ROAS numbers are frequently inflated and misleading. MER is unaffected by attribution models or tracking changes because it uses raw totals from your store and your ad accounts.
What is a good MER for ecommerce?
A good MER depends on your gross margins and business model. As a general benchmark: under 2x is unsustainable for most businesses; 2-3x is a warning zone; 3-5x is considered healthy for physical goods ecommerce; 5-8x is strong; 8x and above is exceptional, usually indicating significant organic revenue. High-margin businesses (digital products, subscriptions) can be profitable at lower MER than low-margin commodity businesses.
How do I improve my Marketing Efficiency Ratio?
There are four main levers: (1) Increase revenue without increasing ad spend - improve conversion rate, average order value, and repeat purchase rate; (2) Reduce ad spend on underperforming channels while maintaining revenue; (3) Build organic revenue through SEO, email, and SMS so more revenue is generated without incremental ad spend; (4) Improve product margins so the business is profitable at a lower MER threshold. The fastest short-term move is usually auditing each channel and cutting or pausing the weakest performer.
Why is MER more reliable than platform-reported ROAS?
Platform-reported ROAS relies on attribution - tracking which ad caused which sale. Since Apple's iOS 14 privacy changes, pixel-based attribution has become significantly less reliable. Platforms also use different attribution windows and models, meaning the same sale is often counted by multiple platforms simultaneously. MER bypasses attribution entirely - you compare total revenue in your store to total spend across all ad accounts. It cannot be gamed by attribution discrepancies.
How does organic revenue affect MER?
Organic revenue - from SEO, email, repeat purchases, and direct traffic - is included in the MER calculation's revenue numerator but not attributed to any ad spend. This means strong organic channels make your MER look better. This is actually correct: organic revenue is a genuine business asset. However, it also means a high MER might reflect good organic performance rather than efficient paid advertising. Always track organic share alongside MER to understand the full picture.