YouTube Ads for e-commerce: formats, targeting, and realistic CPA

Alex Nogueira · 2026-10-07

In-stream vs shorts

On YouTube, you have two main format options: in-stream ads and Shorts.

• In-stream ads are the ones that appear before, during, or after videos. They can be skippable (5 seconds) or non-skippable (up to 15-20 seconds). Ideal for longer, more detailed messaging.

• Shorts are vertical videos up to 60 seconds long, focused on quick, dynamic content. They stand out for engagement and audience attention, making them great for campaigns aiming for quick conversions.

Choose between them based on your goal. If you need to explain a more complex product, go with in-stream. If the idea is to grab attention quickly, Shorts may be more effective.

Custom audiences

Getting your targeting right is crucial. Use custom audiences to increase your chances of converting:

• Customer lists: upload existing customer lists to create a similar audience.

• Retargeting: target users who have already interacted with your site or ads, increasing the likelihood of conversion.

• Interest targeting: choose interests relevant to your niche. For example, if you sell beauty products, target audiences interested in cosmetics.

15- to 30-second video

The ideal ad video is between 15 and 30 seconds long. That’s enough time to present your offer without losing the viewer’s attention.

• Start with a clear call to action in the first 5 seconds.

• Show the product in use and highlight its benefits.

• Include a direct link or QR code to make converting easier.

Bidding

Set your bid based on the strategy you want to follow:

• CPC (Cost per Click): ideal for campaigns aiming to drive clicks to your site.

• CPV (Cost per View): use this if getting video views is the priority.

• CPA (Cost per Acquisition): if you already have a conversion history, this can be a good strategy since it automatically optimizes for conversions.

Run A/B tests to find out which bidding strategy delivers better results.

Measurement

Track your ad performance using Google Analytics and YouTube Analytics. Pay attention to metrics like:

• Click-through rate (CTR): shows how effective your ad is.

• Cost per acquisition (CPA): essential for understanding your return on investment.

• Views and watch time: help you evaluate engagement.

Review this data regularly and adjust your strategy as needed.

What’s the average CPA you’ve been getting with your YouTube ads?