Metric guides
Every metric, one clear page.
Definition, formula, worked examples, and real scenarios — for people who run campaigns or monetize inventory.
Ad Density
Ad Density
Ad Density measures the proportion of a page or screen area occupied by ads ver…
AOV
Average Order Value (AOV)
Average Order Value (AOV) measures the average revenue generated per order plac…
ARPU
Average Revenue Per User (ARPU)
ARPU (Average Revenue Per User) measures the revenue generated per user or subs…
Attribution
Attribution (Conversion Attribution)
Attribution is the set of rules that determines which touchpoints in a customer…
Bid Request
Bid Request (OpenRTB)
A Bid Request is the message an ad exchange sends to bidders (DSPs) to describe…
Bid Response
Bid Response (Bid Resp)
Bid Response is the message a bidder sends back to an exchange after receiving…
Budget Pacing
Budget Pacing
Budget Pacing is the rate at which a campaign spends its daily or lifetime budg…
CAC
Customer Acquisition Cost (CAC)
Customer Acquisition Cost (CAC) is the total cost of convincing a prospect to b…
CPA
Cost Per Acquisition (CPA)
Cost Per Acquisition (CPA) measures the total advertising cost divided by the n…
CPC
Cost per click (CPC)
ad spend / clicks
CPI
Cost Per Install (CPI)
CPI measures the cost to acquire one app install.
CPL
Cost Per Lead (CPL)
Cost Per Lead (CPL) measures how much you spend to acquire one lead — a person…
CPM
Cost Per Mille (CPM)
ad spend / impressions × 1000
CTR
Click-through rate (CTR)
clicks / impressions × 100
CVR
Conversion Rate (CVR)
conversions / clicks × 100
eCPM
Effective Cost Per Mille (eCPM)
revenue / impressions × 1000
Engagement Rate
Engagement Rate (ER)
Engagement Rate measures how often people interact with your ad after seeing it.
Fill Rate
Fill Rate
filled ads / ad requests
First-Price Auction
First-Price Auction
In a first-price auction, the winning bidder pays exactly the amount they bid (…
Floor Price
Floor Price (Reserve Price)
Floor Price (also called reserve price) is the minimum bid an exchange or publi…
Frequency
Frequency (Average Frequency)
Frequency measures how many times, on average, a unique user saw your ad during…
Impression
Impression
An impression is counted each time an ad is fetched and displayed to a user, pe…
IVT Rate
Invalid Traffic Rate (IVT Rate)
IVT Rate measures the share of ad impressions flagged as invalid traffic — non-…
Auction Latency
Auction Latency
Auction Latency measures the time from when a bid request is sent to when the a…
LTV
Lifetime Value (LTV)
Lifetime Value (LTV) estimates the total net revenue a single customer (or coho…
Match Rate
Match Rate
Match Rate measures the share of ad requests that receive at least one bid resp…
Quality Score
Quality Score (QS)
Quality Score is Google Ads’ 1–10 diagnostic for keyword-level expected CTR, ad…
Reach
Reach (Unique Reach)
Reach is the estimated number of unique people who saw your ad at least once du…
ROAS
Return on Ad Spend (ROAS)
revenue / ad spend
ROI
Return on Investment (ROI)
Return on Investment (ROI) measures the net profit generated by an advertising…
RPM
Revenue per Mille (RPM)
revenue / pageviews × 1000
Second-Price Auction
Second-Price Auction
Second-Price Auction is a bidding mechanism where the winning bidder pays the p…
Session RPM
Session RPM (Revenue Per Mille Sessions)
Session RPM (Revenue Per Mille Sessions) measures estimated earnings per thousa…
Take Rate
Take Rate (Platform Fee Share)
Take Rate is the percentage of transaction value that an ad platform (SSP, exch…
Viewability
Viewability (Visible Impression Rate)
Viewability measures whether an ad had a reasonable chance of being seen by a h…
Win Rate
Win Rate
Win Rate is the percentage of auctions in which a bidder wins the impression.