Facebook Ads Metrics Glossary: ROAS, CPA, CPM, CTR and More

This glossary covers the Facebook (Meta) ads metrics you see in Ads Manager and in PixlBridge. For each one you get the formula, one plain sentence on what it tells you, and where PixlBridge shows it. The names follow Meta's own, so you can match them with the columns in Ads Manager.

Quick reference

Return metrics

ROAS (return on ad spend)

Formula: purchase value ÷ ad spend

How many dollars of sales came back for every $1 spent on ads: 3.20× means $3.20 for every $1. Whether a ROAS makes money depends on your margin; the ROAS guide shows how to work out your break-even ROAS.

In PixlBridge: the Ads page, for the account and for every campaign, ad set and ad, as Meta reports it.

Blended ROAS (MER)

Formula: total store revenue ÷ total ad spend

Whether advertising pays for the business as a whole, without relying on attribution. Also called MER, the marketing efficiency ratio.

In PixlBridge: Home, the Blended ROAS card: your Shopify revenue ÷ your Meta ad spend, with the plain line “$3.20 back for every $1”.

Purchases and purchase value

The orders Meta credits to your ads within the attribution window, and what they were worth. Purchase value is the top half of the ROAS formula.

In PixlBridge: the Ads page, per campaign, ad set and ad.

AOV (average order value)

Formula: revenue ÷ orders

What one order is worth on average. Raising it, with bundles or a free-shipping threshold, raises ROAS at the same cost per purchase.

In PixlBridge: the Shopify page, with its trend by day.

Cost metrics

CPA (cost per purchase)

Formula: ad spend ÷ purchases

What each purchase cost you in ads. Compare it with the gross profit on an average order: if CPA is higher, each sale loses money on the first order.

In PixlBridge: the Ads page, as Cost per purchase (CPA).

CPC (cost per click)

Formula: ad spend ÷ clicks (all)

What one click cost on average. Ads Manager also offers CPC (cost per link click), which divides by link clicks only, so it is never lower.

In PixlBridge: the Ads page. PixlBridge's CPC uses all clicks.

CPM (cost per mille)

Formula: ad spend ÷ impressions × 1,000

What it cost to show your ads 1,000 times. It is driven by competition in the auction and by the audience you target, not only by the ad itself.

In PixlBridge: the Ads page.

Delivery metrics

Impressions

How many times your ads were shown on screen. One person can account for several impressions.

In PixlBridge: the Ads page.

Reach

How many different people saw your ads at least once.

In PixlBridge: the Ads page. Reach cannot be added up across days, because the same person appears in several, so PixlBridge asks Meta for the period's reach directly.

Frequency

Formula: impressions ÷ reach

How many times, on average, each person saw your ads. Frequency rising while CTR falls is a common sign that people are tired of a creative.

In PixlBridge: the Ads page, plus a frequency vs CTR chart of your creatives to spot ad fatigue.

Click and engagement metrics

CTR (all)

Formula: clicks (all) ÷ impressions

The share of impressions that got any click, including clicks that did not go to your store, such as clicks to your Facebook Page or to expand the image.

In PixlBridge: the Ads page.

CTR (link)

Formula: link clicks ÷ impressions

The share of impressions that sent someone to your store. It is the better measure of whether an ad drives traffic.

In PixlBridge: the Ads page.

Landing page views

Ad clicks where the person waited for the landing page to load, as counted by the Meta Pixel on that page. A big gap between link clicks and landing page views points at a slow or broken page, or at a pixel that is blocked or missing, so check the pixel first.

In PixlBridge: the Ads page and its funnel. “Why no sale?” compares link clicks with landing page views for each ad.

Video plays and ThruPlays

Video plays count how often a video ad started. A ThruPlay is a play to the end of the video, or of at least 15 seconds.

In PixlBridge: the Ads page.

Store metrics

Conversion rate

Formula: buyers ÷ visitors

Out of every 100 people who visited your store, how many bought. PixlBridge counts unique visitors and buyers from your store's own events, not from Meta's attribution.

In PixlBridge: Home, and the Shopify page's funnel, split by device and by landing page.

Add-to-cart rate

Formula: adds to cart ÷ product views

Of the times people looked at a product, how often it went into the cart. A low rate points at the product page rather than the ad.

In PixlBridge: the Shopify page's products table.

Tracking metrics

Event Match Quality (EMQ)

Meta's score from 0 to 10 for how well the customer information on your server events lets it match them to Meta accounts. See the Event Match Quality guide.

In PixlBridge: Meta's score is in Events Manager. My store shows a match score worked out from the match keys on the events PixlBridge sends, and which keys are present.

Attribution window

The time after a click on, or a view of, an ad in which Meta will credit a purchase to it, for example 7-day click and 1-day view. It decides which purchases count as “from your ads”, so it changes Purchases, purchase value, CPA and ROAS.

In PixlBridge: numbers on the Ads page follow Meta's attribution. The Blended ROAS on Home uses your store revenue, so it does not depend on any window.

Summary

Most of these metrics are ratios of a handful of raw numbers: ad spend, impressions, reach, clicks, link clicks, landing page views, purchases and purchase value on the ad side; visitors, buyers, orders and revenue on the store side. Read the cost metrics (CPM, CPC, CPA) next to the return metrics (ROAS, AOV), and the ad-side metrics (CTR) next to the store-side ones (conversion rate), and most problems show up quickly. When the store side is where people stop, the traffic but no sales guide walks through each funnel step, and PixlBridge for Meta ads puts both sides on one dashboard.