Tools
MER calculator: calculate your marketing efficiency ratio
MER (marketing efficiency ratio) measures your entire marketing against your entire revenue – regardless of what individual platforms claim for themselves. Our north-star metric.
Your MER
All channels combined – paid social, Google, influencers, agency and tool costs.
For the aMER (acquisition MER): how efficiently your spend creates new-customer revenue.
MER
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- aMER (new customers)
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Fill in the fields – the result appears instantly.
Your MER is –: every marketing euro creates – in revenue across all channels. Watch the trend over months – it reveals more than any campaign ROAS.
Runs entirely in your browser – no sign-up, nothing stored.
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Rather have us look at the account directly?
Calculators show you the theory – the free account check shows what your ad account leaves on the table in practice. Including 3 concrete quick wins.
Formula & example
The MER formula
MER deliberately calculates blended – no attribution model, incorruptible:
MER = total revenue ÷ total marketing spend
Example
- €100,000 total revenue ÷ €25,000 marketing spend = MER 4.0
- aMER: €60,000 new-customer revenue ÷ €25,000 = 2.4 – your spend primarily drives acquisition.
Next step in the funnel
Efficiency is covered – but what does a new customer cost?
CAC translates your marketing spend into cost per new customer – and against LTV you'll see whether your growth is financed healthily.
Related content
FAQ
Frequently asked questions
Do agency and tool costs count in the MER calculation?
For the honest full-cost view: yes. Counting media spend only flatters your efficiency. What matters is defining it once and keeping it consistent – otherwise month-over-month comparisons are worthless.
Which period should I choose for the MER?
At least a calendar month – shorter windows fluctuate too much through paydays, drops or sale phases. For trend monitoring, compare rolling monthly and quarterly values.
Which revenue belongs in the aMER?
Only revenue from first-time buyers in the period. That shows how efficiently your marketing actually wins new customers, while the classic MER is propped up by repeat-customer revenue.