CTR — Click-Through Rate
The percentage of people who click on your video after seeing its thumbnail. If YouTube shows your video 1,000 times and 50 people click, your CTR is 5%. This is the single most important metric for algorithmic growth. A CTR above 4% is healthy; above 8% is excellent.
RPM — Revenue Per Mille
The money you earn per 1,000 video views, after YouTube takes its 45% cut. This is the metric that actually matters for your income, not CPM. RPM in the US ranges from $1.50 (entertainment) to $25+ (finance/investing).
CPM — Cost Per Mille
The amount advertisers pay per 1,000 ad impressions. CPM is what advertisers pay; RPM is what you receive. YouTube keeps 45%, so your RPM is roughly 55% of CPM. US CPMs are 3–8x higher than CPMs in Spanish-speaking markets.
AVD — Average View Duration
The average amount of time viewers watch your video. A high CTR paired with a low AVD signals clickbait and gets penalized. The golden combination is CTR above 8% + AVD above 50% for videos around 10 minutes.
Impressions
The number of times YouTube shows your thumbnail to users. Impressions × CTR = Views. The algorithm controls how many impressions you get based on your CTR performance in the first 24–48 hours.
Seed Audience
The small group of your most active subscribers YouTube shows your new video to first. Their click behavior in the first few hours determines whether the algorithm expands distribution or kills the video.
Curiosity Gap
A design principle where the thumbnail poses a visual question the viewer can only answer by clicking. Instead of showing the conclusion, you show the reaction, the before, or an incomplete puzzle. Used by MrBeast and top creators to drive 10%+ CTR.
Tier 1 Countries
The highest-paying advertising markets: United States, United Kingdom, Canada, Australia, and New Zealand. A viewer from the US in a finance niche can be worth $0.025+ per view, while a viewer from a Tier 3 country might be worth $0.001.