Finally, select your audience size. When creating a Facebook Lookalike Audience, you can choose between a range of 1%-10% of the total population in your chosen target country, with 1% being those who most closely match your source. Build towards higher percentage Lookalikes from there as each audience meets your efficiency goals.Once you have your Lookalike audiences built and you’re ready to start using them in your campaigns, you will want to make sure and exclude other Lookalike audiences so you can arrive at the marginal reach for each audience.
We also tested Mobile vs. Smaller audiences more closely match your source audience. The tradeoff is less visibility and control  for more audience relevance and scale.

To scale, you need big audiences. Select audience size. […][…] conducted a $1500 test on Facebook to analyze the performance of lookalike audiences. Learn more, including about available controls: lookalike_spec.country. This is an extremely powerful marketing tool to attract high-converting users via Facebook ads.. When you’re mapping out your Lookalike strategy, always start with a 1% audience since it’s going to be the most relevant. This can mask the importance of optimizing seed audience size since a seed audience of 500 people will provide about the same reach as a seed audience of 5,000 people. Thanks for catching that, and we are now gonna fix it. When choosing an audience for your Facebook ads, “lookalikes” is a segmentation tool that finds users with demographics and interests similar to your existing followers. You can create these source (custom) audiences by going to your You can create your own source audiences using data from: to your website to track users. While segmenting seed audiences this way can give you greater reach than lumping them together, some of this effect will be canceled out by audience overlap, which is important to keep in mind. Audience sizes range from 1% to 10% of the total population in the country you choose, with 1% being those who most closely match your source. Facebook Twitter LinkedIn PinterestFacebook Lookalike Audiences are an excellent way to reach people who are similar to your existing customers and followers. While the 1% and the 5% Lookalike Audiences had a CTR of 0.82%, the 10% Lookalike Audience delivered a CTR of 0.66%. This is what I realized after viewing the data:This would also hold true and explain that forms are more aesthetically pleasing to the eye and user engagement increases as a result especially on mobile devices. ... For example, a Lookalike audience with a seed audience of 10,000 will have a reach that is only a fraction of the size of four Lookalike audiences based on seed audiences of 2,500 ... Facebook Lookalike audiences challenge that assumption. My experience comes from a background in web-design and pages with forms are displayed much more clearly when the page is viewed upright on mobile devices.Will keep in mind to test mobile placements even further in the future. Get the latest news for advertisers and more on our To help personalize content, tailor and measure ads, and provide a safer experience, we use cookies. Creating a larger audience increases your potential reach, but reduces the level of similarity between the Lookalike Audience and source audience.
This can happen when you create multiple Lookalikes from similar seed audiences. This data allows for a wide array of targeting methods for advertisers on Facebook. – TimThis is quite a good read. Here are some additional bits of information to consider when creating Lookalike Audiences. It also allows you to specifically define the event you count as a conversion, whether that be an actual purchase/subscription or some event higher in the funnel.

Facebook allows you to choose a sliding scale of similarity from 1% to 10% when building Lookalike audiences.The percentage chosen indicates the portion of Facebook users who are most similar to your seed audience, expressed as a percentage of total Facebook population (by country). inevitable. You can increase your audience size on Facebook at no added cost just by creating a lookalike audience. This time, instead of selecting “Custom Audience” click on “Lookalike Audience”:Next, you can choose your lookalike source, location, and audience (percentage) size. So, if you’re looking to get the best return on ad spend (), let’s examine how Facebook lookalike audiences can do that. If you don’t create a source audience, you can still build a lookalike audience from Facebook’s pre-determined data sources. So we should target 1% of the people that can be potential buyers.This is extremely interesting.