Glossary

Online advertising metrics, explained in plain language

Every metric from the HeyMetrix monitoring tables, defined the way we'd explain it to a client: what it is, how it's calculated, how to read it, and where it misleads. Google Ads, Meta Ads, and Google Analytics 4.

Ads metrics (Google Ads & Meta Ads)

Impressions →

Impressions count how often your ad was displayed, regardless of whether anyone clicked or even consciously saw it. Every appearance on a search results page, feed, or placement counts once. Impressions are the top of the advertising funnel: without them, no clicks, no conversions.

Clicks →

Clicks count how often someone clicked on your ad. A click is the first active decision in the funnel: a user chose your ad over everything else on the page. Clicks drive traffic; whether that traffic is worth anything shows up later, in conversions.

CTR (Click-Through Rate) →

CTR (click-through rate) is the percentage of ad impressions that resulted in a click. It measures how well your ad matches what the audience wanted in that moment. A high CTR means the message resonates; a low CTR means the ad, the audience, or the moment is off.

CPC (Cost per Click) →

CPC (cost per click) is the average amount you pay for one click on your ad. It reflects competition for your audience: the more advertisers bid on the same keywords or users, the higher the CPC. It's the price tag on your traffic.

CPM (Cost per Mille) →

CPM (cost per mille) is the price for one thousand ad impressions. It's the standard buying unit for awareness and social campaigns, where you pay for visibility rather than clicks. CPM tells you how expensive it is to be seen by your audience.

Cost / Spend →

Cost (or spend) is the total amount an ad platform charged for a campaign, ad group, or account in the selected period. It's the denominator of every efficiency metric (CPC, CPA, ROAS) and the number that has to match the client's media budget.

Conversions →

Conversions count how often users completed the action you defined as valuable (a purchase, lead form, call, or signup) after interacting with your ad. Conversions are the metric campaigns are ultimately judged by, because they connect ad spend to business outcomes.

Conversion Rate →

Conversion rate is the percentage of clicks (or interactions) that ended in a conversion. It measures what happens after the click: landing page quality, offer strength, and audience intent combined. It's the multiplier that decides whether traffic becomes results.

CPA (Cost per Acquisition) →

CPA (cost per acquisition, also cost per conversion) is the average amount you spend to get one conversion. It's the efficiency metric for lead and signup campaigns: as long as a customer is worth more than their CPA, the campaign makes economic sense.

ROAS (Return on Ad Spend) →

ROAS (return on ad spend) is the revenue generated per unit of ad spend: a ROAS of 4 means €4 of tracked revenue per €1 spent. It's the core efficiency metric for e-commerce campaigns, connecting spend directly to the money it brought back.

Conversion Value →

Conversion value is the total monetary value the platform attributes to your conversions: typically order revenue in e-commerce, or values you assign to leads. It's the numerator of ROAS and the basis for value-based bidding strategies.

AOV (Average Order Value) →

AOV (average order value) is the average revenue per conversion: conversion value divided by conversions. It shows what a typical tracked order is worth and helps decide how much a click or conversion may cost before a campaign stops paying off.

Reach →

Reach counts the number of unique people who saw your ad at least once, as opposed to impressions, which count every display. Reach answers 'how many different people did we touch?', the core question of awareness campaigns, primarily reported on Meta.

Frequency →

Frequency is the average number of times each reached person saw your ad: impressions divided by reach. It measures repetition: some repetition builds memory, too much burns budget and goodwill. Frequency is the early-warning metric for creative fatigue on Meta.

Results (Meta) →

Results is Meta's umbrella metric for the outcome a campaign was optimized for: purchases for a sales campaign, leads for a lead campaign, link clicks for a traffic campaign. The same column means different things across campaigns, depending on each campaign's objective.

Cost per Result (Meta) →

Cost per result is Meta's efficiency metric: total spend divided by results, where 'result' is whatever the campaign optimizes for. For a sales campaign it equals cost per purchase; for a traffic campaign, cost per link click. It's Meta's generalized CPA.

Website metrics (Google Analytics 4)

Active Users (GA4) →

Active users is GA4's primary user metric: the number of distinct people who had an engaged session or fired a first-visit/engagement event in the period. It replaced Universal Analytics' 'users' as the default headcount of your website audience.

Sessions (GA4) →

A session is one visit to your website: it starts when a user arrives and ends after 30 minutes of inactivity. One user can have many sessions. Sessions measure visit volume, the standard unit for 'how much traffic did the campaign send?'.

Page Views (GA4) →

Page views count every time a page on your site is loaded or reloaded. They measure raw content consumption: which pages get seen, how deep visitors go. Divided by sessions, they show how many pages a typical visit covers.

Key Events (GA4) →

Key events are the GA4 events you marked as most valuable: purchases, sign-ups, contact form submissions. They are GA4's successor to 'conversions' (renamed in 2024) and the website-side counterpart to your ad platforms' conversion tracking.

Engagement Rate (GA4) →

Engagement rate is the share of sessions that were 'engaged': lasted over 10 seconds, had a key event, or included at least two page views. It's GA4's inverse of the old bounce rate: it measures how many visits showed any real interaction.

Avg. Session Duration (GA4) →

Average session duration is the mean time visitors spent on your site per session. It approximates depth of interest: longer sessions usually mean content that holds attention. For ad traffic, it shows whether clicks brought people who actually wanted to be there.

Metrics explained are nice. Metrics watched are better.

HeyMetrix monitors all of these across Google and Meta, with alerts and a nightly AI briefing.

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