ReferenceNo. 13
A Field Guide to Marketing Metrics
Key takeaways
- Honest CAC includes salaries, tools, and fees, not just media spend.
- Net revenue retention can exceed 100%, while gross retention never can.
- A metric only earns its place if a good or bad reading changes a decision.
Marketing runs on a small set of numbers that show up in every board deck and every weekly standup, and most of them are easy to define wrong. This guide collects the metrics that actually drive decisions, with plain definitions a marketer can use without a finance background. Where a number is commonly misread, there is a short note on the trap.
Acquisition and cost
- CAC. Customer acquisition cost is the total sales and marketing spend over a period divided by the number of new customers won in that period. The honest version includes salaries, tools, and agency fees, not just ad budget. A CAC that only counts media spend will always look better than reality.
- Blended vs paid CAC. Blended CAC divides total acquisition spend by all new customers, including those who arrived through organic, referral, or word of mouth. Paid CAC counts only customers attributed to paid channels against paid spend. Blended looks cheaper because free customers subsidize the average, so use paid CAC when you are judging whether a paid channel is worth scaling.
- CPA. Cost per acquisition is the spend divided by a defined conversion action, which may be a signup, a trial, or a lead rather than a paying customer. It is often used interchangeably with CAC, which causes confusion, so always confirm what the "A" refers to before comparing two numbers.
- Payback period. The time it takes for the gross margin from a customer to repay the cost of acquiring them, usually measured in months. Shorter payback means cash comes back faster and growth can self-fund. People often quote payback on revenue instead of gross margin, which understates how long the money is actually out.
Revenue and retention
- LTV. Lifetime value is the total gross margin you expect to earn from a customer across the whole relationship. The common mistake is to use revenue instead of margin, or to assume a customer lifetime far longer than your retention data supports. Treat any LTV built on optimistic churn assumptions with care.
- LTV to CAC ratio. This compares the value of a customer to the cost of winning them. A ratio around three to one is often cited as healthy, meaning each customer returns roughly three times what they cost to acquire, though the right target depends on margins and payback. A very high ratio is not always good news, because it can mean you are underspending and leaving growth on the table.
- ARPU. Average revenue per user is total revenue in a period divided by the number of users or accounts. It is a quick read on monetization, but averages hide the spread, so a few large accounts can make a weak base look healthier than it is.
- MRR and ARR. Monthly recurring revenue is the predictable subscription revenue normalized to a month, and annual recurring revenue is the same figure annualized. One time fees and usage spikes do not belong in either, since the whole point is the recurring base you can count on.
- Gross vs net revenue retention. Gross revenue retention measures how much recurring revenue you keep from existing customers over a period, counting only losses from churn and downgrades, so it can never exceed 100%. Net revenue retention adds expansion from upgrades and cross sells, so it can exceed 100% when existing customers grow faster than others leave. Reporting net retention while calling it gross is a common way to flatter a churn problem.
- Logo churn vs revenue churn. Logo churn is the share of customers (logos) that leave in a period. Revenue churn is the share of revenue lost. They diverge when your departing customers are not average in size, so losing many small accounts can look alarming on logo churn while barely touching revenue, and losing one large account does the reverse.
Funnel and conversion
- Conversion rate. The share of people who take a desired action out of those who had the chance, such as visitors who buy or trials who upgrade. It is only meaningful when the numerator and denominator describe the same step, and comparing conversion rates across stages with different definitions is a frequent error.
- MQL and SQL. A marketing qualified lead is a contact that marketing judges interesting enough to pursue, usually from behavior or fit. A sales qualified lead is one that sales has accepted as worth active selling. The gap between the two counts is one of the most honest signals of whether marketing and sales agree on what a good lead looks like.
- Win rate. The share of qualified opportunities that close as won. It is sensitive to how you define a qualified opportunity, so a team can lift its win rate simply by disqualifying weaker deals earlier rather than by selling better.
- Average deal size. The mean revenue per closed deal, often shown as annual contract value or first year value. The average can be pulled around by a few large deals, so the median is frequently the more useful number for planning.
- Pipeline and pipeline coverage. Pipeline is the total value of open opportunities expected to close in a period. Pipeline coverage is that pipeline divided by the revenue target for the period, and a figure around three times target is commonly cited as a working rule. Coverage means little if the underlying win rate and deal sizes baked into it are stale.
Advertising
| CTR | Click through rate is clicks divided by impressions, expressed as a percentage. A high CTR shows the creative and targeting earned attention, but it says nothing about whether those clicks turned into anything valuable. |
| CPM | Cost per mille is the cost to serve one thousand ad impressions. It is a buying and efficiency measure for reach, not a performance measure, since cheap impressions that nobody acts on are still wasted. |
| CPC | Cost per click is the spend divided by clicks. It tells you what traffic costs, not what that traffic is worth, so a low CPC paired with poor conversion can be more expensive in the end than pricier, better qualified clicks. |
| ROAS | Return on ad spend is revenue attributed to advertising divided by the cost of that advertising, usually shown as a ratio or multiple. It depends entirely on the attribution behind it, and it ignores margin, so a strong ROAS on low margin products can still lose money. |
| Attribution | The method used to assign credit for a conversion across the touchpoints that preceded it. It shapes almost every channel number above, and it has its own article, so treat it as the assumption layer rather than a metric. |
Brand and loyalty
- NPS. Net promoter score asks how likely someone is to recommend you on a zero to ten scale, then subtracts the share of detractors (zero to six) from the share of promoters (nine to ten). It is a directional read on sentiment, not a precise gauge, and small sample sizes make it swing more than people assume.
- CSAT. Customer satisfaction score captures how satisfied someone was with a specific interaction or purchase, usually as the share of responses at the top of a short rating scale. It measures a moment rather than the whole relationship, so a strong CSAT on support tickets can coexist with customers who are quietly leaving.
The rule that ties them together
A metric only earns its place if it changes a decision. Numbers that get reported every week but never alter what the team does next are decoration, and they crowd out the few that should. Before adopting a metric, name the choice it informs and the action a good or bad reading would trigger. If you cannot, stop measuring it and find one that does.
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