A creator glossary of the metrics and terms that get used loosely - RPM, CPM, reach, impressions, engagement rate - defined precisely enough to argue with.
This creator glossary defines the terms that get used loosely in creator conversations, precisely enough that two people using them mean the same thing. Most disagreements about performance turn out to be disagreements about definitions.
Creator glossary: audience and reach
Followers / subscribers. People who opted in. A threshold metric rather than a measure of health — vanity metrics.
Reach. The number of unique accounts that saw a post. Always smaller than followers for most accounts.
Impressions. The number of times a post was displayed, including repeats. Always equal to or larger than reach.
Views. Platform-specific and inconsistent. Some count a fraction of a second, others require several seconds. Never compare view counts across platforms.
Engagement
Engagement rate. Interactions divided by an audience number, times 100. Which audience number changes the answer several-fold — engagement rate and by reach vs by followers.
Interactions. Likes, comments, saves, shares. Which of these you can see depends on the platform and on whether the account is yours.
Saves. The strongest signal on most platforms, because a save implies future intent.
Completion rate. The share of viewers who watched to the end. The dominant signal in short-form.
Retention. The curve of how many viewers remain over a video's length. The dominant signal in long-form.
Watch time. Total time watched. Retention × length × views, and the currency of YouTube's Partner Programme — YouTube monetization requirements.
Money
CPM. Cost per mille — what an advertiser pays per 1,000 ad impressions, before the platform's share.
RPM. Revenue per mille — what you earn per 1,000 video views, after the platform's share and including non-ad income. Always lower than CPM. See RPM vs CPM.
Monetized playbacks. Views where an ad actually ran. Fewer than total views.
Revenue share. The platform's split. YouTube pays 55% of net ad revenue on long-form watch-page ads and 45% of the Shorts pool allocated by view share (YouTube Help).
Rate card. What you charge brands. Negotiated on audience fit rather than calculated from a ratio — social media benchmarks.
Discovery
CTR. Click-through rate — of the people shown your thumbnail or link, how many clicked.
Impressions-to-click. The same thing, phrased to make the denominator explicit.
Suggested / recommended. Distribution the platform chooses, as opposed to search or following.
SEO. On a platform, optimising the fields the ranking system reads — YouTube SEO and Pinterest SEO.
Funnel. The path from someone seeing you to someone doing something. On social it is usually: short-form reach, profile visit, follow, and eventually something off-platform.
Owned audience. People you can reach without a platform's permission - an email list, mostly. The only audience that survives an algorithm change.
Repurposing. Reshaping one piece of work for several formats and platforms - content repurposing.
UTM parameters. Labels on a URL that tell your analytics where a visitor came from - UTM parameters for creators.
Format terms
Safe zone. The part of a frame not covered by interface — safe zones.
Aspect ratio. The shape of a frame, independent of resolution — aspect ratio.
The fold. Where text is truncated behind "more". Different on every platform.
Open Graph. The metadata that produces link previews — Open Graph tags.
What is the difference between reach and impressions?
Reach counts unique accounts that saw a post; impressions count displays including repeats. Impressions are always equal to or higher.
What is the difference between RPM and CPM?
CPM is what advertisers pay per 1,000 ad impressions before the platform's cut. RPM is your revenue per 1,000 views after it.
Is a view the same on every platform?
No. The threshold for counting a view differs by platform, which makes cross-platform view comparisons meaningless.
What is completion rate?
The share of viewers who watched a video to the end - the dominant ranking signal in short-form video.