Glossary
What is Video completion rate?
Also called: VCR, completion rate, video completion rate
Video completion rate (VCR) is the share of video ad impressions that play to the end: completes divided by impressions.
हिंदी में पढ़ेंCompletion rate, or VCR, comes from the VAST tracking events. The player fires complete when an ad plays to the end, and completion rate is completes divided by impressions. The quartile events before it, at 25%, 50% and 75%, show where viewers dropped off on the way.
Completion depends heavily on placement. An instream ad, playing before or during video the viewer chose to watch, is a different experience from an outstream player that starts between paragraphs as the reader scrolls. The IAB’s plcmt field labels these placements so buyers can bid differently on each, which is why honest labelling matters.
Read completion rate alongside viewability: under the IAB and MRC standard a video ad is viewable when at least 50% of the player is on screen for two continuous seconds. VAST errors, such as 302 or 303, and low fill also mean breaks that earn less than they could.
Example
Say an instream player on video pages logs 9,000 completes from 12,000 impressions: 9,000 ÷ 12,000 = 75%. An outstream player between paragraphs logs 3,000 completes from 10,000 impressions: 30%. Reporting them together would hide the gap.
Why it matters to publishers
Buyers use completion rate to judge video inventory. Tracking it by placement shows which players deliver what buyers pay for.