In-stream ads

What is In-stream ads?

In-stream ads are advertisements embedded directly within video content, appearing before (pre-roll), during (mid-roll), or after (post-roll) the primary video a viewer has chosen to watch. They are a core format in video advertising across mobile, desktop, and connected TV environments, and are commonly served on platforms that monetize content through advertising. Because viewers must engage with the content around them, in-stream ads deliver higher attention than most other digital ad formats.

How it works

In-stream ads function by interrupting or bookending a video stream with an advertisement served through an ad server or programmatic buying system. The video player requests an ad using standards such as VAST (Video Ad Serving Template) or VPAID, which define how the ad is delivered, tracked, and measured.

Pre-roll Ads

Pre-roll ads play before the main video begins. They typically run between 15 and 60 seconds and are often non-skippable for their full duration or for a defined initial window. Because the viewer has just initiated the content, attention is high at this moment, making pre-roll placements effective for awareness and brand messaging.

Mid-roll Ads

Mid-roll ads appear at natural breaks during longer video content, similar to traditional television commercial breaks. Viewers are already invested in the content, which increases the likelihood that they absorb the ad message. Mid-roll placements are particularly common on longer-form content platforms and live streams. The captive context makes this format valuable for deeper engagement goals.

Post-roll Ads

Post-roll ads run after the video content concludes. They reach viewers who have watched the content in full, representing a more committed segment of the audience. While post-roll ads have lower overall reach due to viewer drop-off, those who do see them tend to be highly engaged. Auto-play sequences and creative transitions can improve post-roll performance.

Skippable vs. Non-skippable

In-stream ads are served in both skippable and non-skippable formats. Non-skippable ads force the viewer to watch the full creative before the content plays or resumes. Skippable ads allow the viewer to skip after a short window, typically five seconds, which means advertisers often pay only when a viewer watches past that threshold. The choice between formats involves a trade-off between reach, cost, and forced exposure.

Why it matters

In-stream ads are among the most impactful formats available to digital advertisers because they reach audiences in a high-attention state. Video content consumption on mobile devices continues to grow, and in-stream placements are central to how publishers monetize that consumption through models like AVOD. For performance marketers, in-stream ads support both upper-funnel brand awareness and lower-funnel outcomes such as app installs and product purchases, depending on how the creative and targeting are configured. Metrics such as view-through rate (VTR), cost per completed view (CPCV), and cost per view (CPV) are used to evaluate in-stream campaign efficiency. Attribution for in-stream ads, particularly view-through attribution, allows marketers to credit conversions that occur after an ad impression even without a direct click, making measurement more complete. In mobile contexts, tracking in-stream ad exposure through an MMP enables marketers to connect video impressions to downstream app events, providing a clearer picture of video's contribution to user acquisition and retention.

How to implement in-stream ads in a mobile campaign

1. Define your objective. Determine whether the in-stream placement is serving awareness, consideration, or conversion goals. This informs format choice (skippable vs. non-skippable), creative length, and success metrics.

2. Select the appropriate format. Use pre-roll for broad awareness, mid-roll for engaged audiences on longer content, and post-roll for highly committed viewers. Match format to the content environment and audience intent.

3. Choose your buying method. In-stream inventory can be purchased programmatically through a DSP via real-time bidding, through private marketplace deals, or directly with publishers. Programmatic buying offers scale and targeting precision.

4. Build creatives to spec. In-stream ads follow VAST standards. Ensure your video creative meets the platform's duration, resolution, and bitrate requirements. For non-skippable formats, front-load the key message within the first few seconds.

5. Configure measurement. Implement tracking links or SDK-based measurement through an MMP such as Airbridge to attribute app installs and in-app events back to in-stream impressions. Enable view-through attribution to capture conversions that occur after an impression but without a click.

6. Monitor and optimize. Track VTR, CPCV, CPV, and conversion rate throughout the campaign. Adjust bids, targeting, and creative based on performance data. Use cohort analysis to assess the downstream value of users acquired through in-stream placements.

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