Marketing Efficiency Ratio (MER)

Marketing efficiency ratio (MER) is a high-level ratio often calculated as total revenue divided by advertising spend for the same period. If a company records $80,000 in revenue and spends $10,000 on advertising, the MER is 8.0. Some teams use different definitions of 'marketing spend' or 'revenue', so the inputs and time window should always be stated.

MER offers a broad view of how a business's sales compare with paid media investment. Unlike campaign-level return on ad spend (ROAS), it does not attempt to attribute each sale to a particular advertisement. Organic search, repeat business, referrals, seasonality, promotions, and pricing can all move the numerator without a direct paid-ad effect.

A higher MER is not automatically proof of healthier profit. Labor costs, gross margin, customer acquisition costs, and revenue recognition can change the commercial interpretation. Use MER alongside margin, channel reporting, and longer-term trends instead of treating it as a causal measure of advertising performance.