Ad Guide: In-Stream (Europe)

In-Stream Video Ad Formats

General Information

smartclip’s best practices for video advertising creatives:

  • Aspect ratio: 16:9 (standard widescreen)
  • Video length: 15-25 seconds (recommended)
  • The following setups are not allowed (settings will get applied by smartclip):
    • Automatically expanding ads
    • Inserted “close button”
    • Preset cappings (geo, FC, device, etc.) by campaign/agency 

Subtitles/closed captioning: VAST 4.1 enables subtitles/closed captioning by standardising the delivery of closed captioning files. Please make sure to include closed caption file.

For IO, please provide all creative material or redirects at least 5 days before campaign start. Delayed/incorrect delivery can lead to a delayed starting date of the agreed campaign and a punctual start is no longer guaranteed. Changing ads during the campaign period may only be carried out with tested advertising assets and in accordance with smartclip.

Subject to prior consultation and agreements, other requirements may apply for individual forms of advertising/billing.


Pre-Roll video ads stream directly before the publisher’s content begins. Since Pre-Roll ads precede featured content, they are more likely to be perceived by viewers as informative rather than intrusive, and drive key metrics such as brand awareness, brand engagement, brand favorability, and purchase intent. 

Available on desktop, tablet, mobile, and smart TVs.


Mid-Roll video ads resemble conventional commercial breaks and stream in the middle of the publisher’s video content. Since viewers that make it to a Mid-Roll ad are highly engaged and more likely want to view featured content to the end, this placement typically achieves high completion rates. 

Available on desktop, tablet, mobile, and smart TVs.


Post-Roll video ads stream directly after the publisher’s video content. Since Post-Roll ads follow featured content, they work well if your ad encourages viewers to perform an immediate action, as viewers are more likely to respond to a call-to-action when it does not distract them from the original featured content. 

Available on desktop, tablet, mobile, and smart TVs.

Bumper Ad

Available in all In-Stream environments, played out as a Pre-, Mid- or Post-Roll, the Bumper Ad is a short commercial with a maximum length of 6 seconds. Due to its short, user-friendly format, this ad receives high VTR and works well as a campaign supplement.

Available on desktop, tablet, mobile, and smart TVs.

Technical Specifications

Video File

Please provide a click URL and 
(optional) trackers.

File Type

1920×1080 (recommended), 
min. 1280×720 

Aspect Ratio
16:9 (landscape)

File Size
max. 200 MB


min. 128 Kbps, 44 kHz, Stereo, ACC or MP3 (recommended)

Video Bitrate 
min. 2500 Kbps
Tag / Redirect Delivery

Please supply as a separate text file attachment.

Approved Tags 

TLS (SSL)-enabled

linear VAST tags are accepted
(IAB standards)

only supported as of Javascript

Video Bitrate 
min. 2000 Kbps (CTV); min. 800 Kbps (Desktop/Mobile)

Creative to contain min. a media file 
each of 640×360 and 960×540 

Download our In-Stream Ad Guide here.

Fabian Burgey

Fabian is the Director SME Business Europe and has been working with smartclip since June 2019. He helps smartclip’s international reseller and SME clients leverage Addressable TV and Online-Video Solutions.

Fabian Burgey
Director SME Business Europe

Lisa-Theresia Rischke is the Head of Brand at smartclip Europe and responsible for the smartclip brand. She leads the design team and oversees collateral, social media, and strategic content marketing initiatives across Europe. 

Lisa Rischke
Head of Brand