Facebook is reinstalling reach estimates for Custom Audiences, a tool that allows advertisers to estimate audience size for their Custom Audience campaigns. Back in March of last year, the company removed the tool after researchers at Northwestern University found a vulnerability which made it possible to infer attributes of Facebook users via the tool.

“People’s privacy is incredibly important to Facebook and we take any potential abuse of our service very seriously,” said Facebook Director of Product Management Mary Ku, “Last year, when researchers found this issue, we suspended it and after working with those researchers to address the issue, we are now reinstating it.”

According to Facebook, it worked on three major changes to improve security around its Custom Audiences reach tool:

  • Privacy
  • Detection
  • New restrictions

The new restrictions include Custom Audience rate limits, which is the number of audiences or API calls an account can have. The new rate limits were designed to limit possible misuse. Facebook says that this will not impact most advertisers.

Reach estimates were useful for advertisers, as it made it possible to determine approximate campaign size, manage budges and bidding activity accordingly, all without taking up time and effort on their part.

“When thinking of the last year, the absence of the product didn’t impact the way we crafted and developed strategies, but rather impacted the precision of our strategies,” said 360i Vice President of Paid Social Strategy Lead Phillip Huynh. “Instead of having more precise reach estimates, we often used proxies on our end that needed to be monitored closely to ensure that we didn’t over-under saturate the market,” he added.

According to Huynh, the reintroduction of reach estimates is going to allow his agency to activate “closer” to the data they planned against. This is a boon for both brands and brand audiences on the platform as it helps deliver more relevant ads.

“We’re really excited about having this brought back to the platform as the reach estimate tool allows us to plan more efficiently and effectively,” said Huynh, “It does this by giving us a clear understanding of the size of our audiences on the buying platform, which helps inform ideal budgets and bids.”

SourceAmy Gesenhues