40+ essential terms defined simply, grouped by topic. Every entry has a stable anchor you can share: #roas, #cac, #ltv…
Urchin Tracking Module parameters
Query string tags (utm_source, utm_medium, utm_campaign, utm_content, utm_term) appended to URLs to track campaign attribution in analytics. Without them, the source/medium of a visit can be guessed but not measured.
Organic traffic
Visits from non-paid sources: search engines (SEO), direct, referral, organic social. Usually has higher intent and better CVR than paid, but is harder to scale on demand.
Search Engine Results Page
The page Google (or another engine) returns for a query. Modern SERPs include 10 blue links plus AI overviews, featured snippets, people-also-ask, knowledge panels, video carousels, each is a separate visibility opportunity.
Search Engine Optimization
The discipline of structuring content + technical setup so search engines rank you for relevant queries. Pillars: technical SEO (crawlability, speed), on-page SEO (intent match, structured data), off-page SEO (backlinks, mentions).
Generative Engine Optimization
Optimizing content so that generative AI engines (ChatGPT, Perplexity, Google AI Overview, Claude) cite your brand when users ask related questions. Distinct from SEO because the surface is the AI answer, not the ranked link list.
Conversion Rate
Conversions divided by some upstream count (sessions, clicks, visitors). The exact denominator matters, « checkout CVR » vs « site CVR » are very different numbers.
Conversion funnel
Sequence of steps a user takes from first touch to converted (e.g. landing → product page → cart → checkout → purchase). Bottlenecks are visible as sharp drops between steps.
Bounce rate
% of sessions where the user left without a meaningful interaction. GA4 calculates it as 1 − engagement rate. High bounce on paid landing pages = mismatch between ad creative and landing content.
Marketing Qualified Lead
A lead that marketing considers ready for sales follow-up based on signals (job title, company size, content consumed). Defined per company.
Sales Qualified Lead
A lead that sales has actively engaged and qualified (typically: budget, authority, need, timing confirmed). The next stage after MQL.
Product-Market Fit
The point at which a product satisfies strong market demand. Marketing metrics shift sharply at PMF: organic growth accelerates, paid CAC drops, retention stabilizes.
Churn rate
% of customers (or revenue) lost over a period. Logo churn counts customers; revenue churn weights by value. A 5% monthly churn means you re-acquire half your base every year just to stand still.
Retention rate
% of customers still active at the end of a period (or after N days from signup). The inverse of churn. Cohort retention curves are how you spot whether retention is improving over time.
Cohort analysis
Grouping users by a shared attribute (signup month, acquisition channel, plan) and tracking their behavior over time. Lets you compare apples to apples, January signups in their 3rd month vs March signups in their 3rd month.
Net Revenue Retention
Revenue retained from existing customers, including expansion (upgrades) and net of churn + downgrades. NRR > 100% means you grow even without new customers, the holy grail metric in SaaS.
Cost per Click
Average price paid for one click on your ad. Total spend / total clicks. Direct lever in auction-based bidding (Google Ads, Meta Ads).
Cost per Mille (per thousand impressions)
Price for 1,000 ad impressions. Total spend / (impressions / 1,000). Used for awareness campaigns where the goal is reach, not clicks.
Cost per Lead
Spend required to acquire one lead (form fill, sign-up). Different from CAC because a lead is not yet a customer, most leads will not convert.
Cost per Acquisition (or Action)
Spend per defined conversion event. Often used interchangeably with CAC, but technically CPA can refer to any conversion (add-to-cart, trial start) not just paying customers.
Click-Through Rate
Clicks divided by impressions, expressed as %. High CTR signals creative relevance to the audience. Declining CTR with the same creative over time is the canonical signal of ad fatigue.
Frequency
Average number of times each unique user has seen your ad. Frequency > 3-4 on the same audience usually means diminishing returns and growing audience annoyance.
Reach
Number of unique users who saw your ad at least once. Distinct from impressions, which counts every view including repeats.
Impressions
Total number of times your ad was rendered to a user. Reach × frequency = impressions.
Ad / creative fatigue
Performance decay over time on a static creative as the audience sees it repeatedly. Detected by declining CTR and rising CPM/CPC with stable bidding. Fix: rotate creatives, refresh hooks, expand audience.
Lookalike audience
Audience generated by a platform (Meta, Google) by finding users similar to a source audience (customers, high-LTV users). Sometimes called « similar audience » or « actalike ».
Retargeting / Remarketing
Serving ads to users who already interacted with your brand (visited the site, abandoned a cart, watched a video). Higher conversion rate than prospecting but smaller reach.
Attribution
The set of rules that decide which marketing touchpoint(s) get « credit » for a conversion. The model you pick (last-click, first-click, linear, time-decay, data-driven) materially changes which channels look good or bad.
Last-click attribution
Assigns 100% of the conversion credit to the last touchpoint before conversion. The default in most legacy analytics. Easy to implement, but undercredits awareness and top-of-funnel channels.
Multi-touch attribution
Distributes conversion credit across multiple touchpoints in the path (linear, time-decay, position-based, data-driven). More fair to upper-funnel channels but harder to model. GA4’s default model is data-driven multi-touch.
View-through conversion
A conversion credited to an ad the user saw (impression) but did not click. Common on Meta, easy to inflate, most platforms count any view-through in a 1-7 day window.
Return on Ad Spend
Revenue generated per €1 of ad spend. Calculated as (revenue / ad spend). A ROAS of 4 means €4 in revenue for every €1 spent. Used as a top-line health check on paid campaigns. Distinct from ROI because it ignores costs other than media (e.g. agency fees, COGS).
Return on Investment
Net profit relative to total cost. (Revenue − cost) / cost. Captures the full economics, media + production + agency + COGS, unlike ROAS which only uses media spend.
Customer Acquisition Cost
Total cost of acquiring one paying customer. Total acquisition spend / new customers in the same period. « Blended CAC » includes all channels; « paid CAC » isolates paid media.
Customer Lifetime Value
Total revenue (or profit) a customer is expected to generate during their entire relationship with you. Compared to CAC, the LTV/CAC ratio is the canonical SaaS unit-economics health check, most healthy businesses target 3:1 or better.
Lifetime Value to Customer Acquisition Cost ratio
LTV divided by CAC. <1 means you’re losing money on acquisition. 1–3 is unsustainable. 3+ is healthy. Most VC-backed SaaS aim for >5 at scale.
Monthly Recurring Revenue
Predictable monthly revenue from active subscriptions. Excludes one-time charges and annual upfront payments (those get normalized to monthly equivalent). The core north-star for subscription businesses.
Annual Recurring Revenue
MRR × 12. The annualized view of subscription revenue, used in reporting to investors and for valuation multiples.
Average Order Value
Average revenue per order. Revenue / number of orders. Lifting AOV (bundles, upsells, free-shipping thresholds) is often cheaper than lifting conversion rate.
Google Analytics 4
Google’s current web/app analytics product, replacing Universal Analytics in 2023. Event-based model. Free tier ample for most SMBs; BigQuery integration is the upgrade path.
Google Search Console (GSC)
Google’s free tool reporting how your site performs in Google search results, queries, impressions, clicks, CTR, average position. The ground truth for SEO performance, more reliable than third-party rank trackers.
Key Performance Indicator
A metric explicitly chosen because hitting a target on it indicates business success. The discipline is in « explicitly chosen », without it, every metric becomes a KPI and none of them matter.
Tracking pixel
A 1×1 image (or JavaScript snippet) loaded on a page to register an event with an ad platform. The Meta Pixel and Google tag are the dominant ones in performance marketing. Increasingly augmented or replaced by server-side conversions APIs for privacy resilience.
Customer Data Platform
Software that unifies customer data from multiple sources (CRM, app, web, support) into one persistent profile per user, then routes that data to downstream tools (ads, email, analytics). Examples: Segment, Rudderstack, Hightouch.