Marketing metrics in plain language.

Marketing metrics are the numbers that measure how well your ads perform at every stage — from impression to profit. There are ten key ones: CPM and CPC track the cost of traffic, CTR and CR track conversion, CPL and CAC track the cost of a lead and a customer, while ROAS, ROMI, ad spend ratio, and LTV track the money advertising brings in. Below, you'll find each metric with its formula and an example.

CPM (Cost Per Mille) is the cost per thousand ad impressions. It doesn't tell you whether people are buying, only how much it costs to "reach" the audience. The narrower and more competitive the audience, the higher the CPM. It's used to evaluate reach and compare channels against each other.

Formula: CPM = (Spend ÷ Impressions) × 1000. Example: a $50 budget and 25,000 impressions give a CPM of $2. That means a thousand impressions of your banner cost you two dollars.

CPC (Cost Per Click) is the average cost of one click on an ad. It shows how much it costs to bring someone to your site or profile. Unlike CPM, you're paying for an action, not an impression. A low CPC with poor conversion still burns through your budget, so read this metric alongside CR.

Formula: CPC = Spend ÷ Clicks. Example: a $100 budget and 250 clicks give a CPC of $0.40. Each visit to your landing page cost you forty cents.

CTR (Click-Through Rate) is the percentage of people who clicked out of those who saw the ad. It's the main indicator of how well the creative and offer resonate with the audience. A high CTR lowers the cost of impressions and clicks, because Meta's and Google's algorithms reward relevant ads with a lower auction price.

Formula: CTR = (Clicks ÷ Impressions) × 100%. Example: 250 clicks out of 25,000 impressions is a CTR of 1%. On Meta, 1–2% is considered average; anything higher points to a strong creative.

CR (Conversion Rate) is the share of visitors who completed the target action: submitted a form, booked, or bought. This metric reflects the quality of the landing page and offer, not the ad itself. Even cheap traffic is worthless if the page doesn't convert, which is why CR is the bridge between a click and revenue.

Formula: CR = (Conversions ÷ Visitors) × 100%. Example: 50 form submissions out of 1,000 visitors give a CR of 5%. Raising CR is often cheaper than lowering the cost of traffic.

CPL (Cost Per Lead) is the cost of one lead: a form submission, sign-up, or DM inquiry. It's the most popular metric for lead generation, since it immediately shows the cost of a potential customer. But looking at it in isolation is risky — the share of qualified leads matters just as much as the price.

Formula: CPL = Spend ÷ Number of Leads. Example: in our B2B case with medical devices, a 10-day test delivered 96 leads at a CPL of $1.95. In a fitness case in Kazakhstan — CPL of $2.06 and 90% qualified leads.

CAC (Customer Acquisition Cost) is the cost of acquiring one actual paying customer. Unlike CPL, CAC accounts for the whole funnel: not every lead buys, so CAC is always higher. CAC, not CPL, is what answers the question "how much does a customer cost us."

Formula: CAC = Marketing Spend ÷ Number of New Customers. Example: at a CPL of $1.95 and a lead-to-payment conversion of 30%, CAC comes out to about $6.5. CAC only makes sense when compared against LTV.

ROAS (Return On Ad Spend) is how much revenue the ads generated for every dollar spent. It's the fastest way to see whether a campaign is paying off. ROAS doesn't account for the cost of goods, so it's a gross, not a net, payback figure — but it's indispensable for a quick read on ad performance.

Formula: ROAS = Ad Revenue ÷ Ad Spend. Example: in a restaurant chain case, a $145 budget turned into $7.5K in revenue — a ROAS of 51.7× over 10 days. For more on the calculation, see the guide how to calculate ROAS.

ROMI (Return On Marketing Investment) is marketing payback that accounts for cost of goods. Where ROAS calculates gross revenue, ROMI takes net profit, so it more accurately answers whether the business actually made money. Ad spend ratio (the share of revenue spent on ads) is the inverse of ROAS: what percentage of revenue went toward advertising.

Formulas: ROMI = ((Profit − Spend) ÷ Spend) × 100%; Ad spend ratio = (Ad Spend ÷ Revenue) × 100%. Example: a ROAS of 5× equals an ad spend ratio of 20% — the ads "ate up" a fifth of the revenue.

LTV (Lifetime Value) is the total profit from one customer over the entire time they work with you. LTV is what shows how much you can realistically spend on acquisition. In niches with repeat purchases (beauty, coffee shops, fitness), one customer comes back many times, so a high cost for the first purchase is justified.

Formula (simplified): LTV = Average Order Value × Number of Purchases × Duration of Relationship. Benchmark: a healthy business maintains an LTV-to-CAC ratio of at least 3:1. If LTV is $300 and CAC is $50, the model is stably profitable.

No single metric evaluates a business on its own. A low CPL without CR and CAC is misleading, a high CTR without conversions doesn't make money, and ROAS without LTV doesn't show the real payback. At InSync, we read them as a chain: impression → click → lead → customer → repeat purchases. Over 4 years, 150+ projects, and $200K+ in managed ad spend, we've built this approach into weekly reports where every number has context. Read more on choosing a contractor in our article on agency vs. freelancer.