Custom Audiences

Custom Audiences are audience segments you create in Google Ads by specifying keywords, website URLs, and apps that your ideal customers are likely to search for, browse, or use. Google then identifies users who match those behavioral signals and makes them available for targeting across Display, YouTube, Discovery, and Performance Max campaigns.

Key Takeaways

• Custom Audiences replace the legacy Custom Intent and Custom Affinity audiences
• Built from three signal types: search keywords, website URLs, and apps
• Available on Display, YouTube, Discovery, and Performance Max campaigns (not standard Search)
• Google automatically interprets signals as either interest-based or intent-based depending on campaign type
• Provide more precision than predefined Audience Segments for niche markets

What Are Custom Audiences

Custom Audiences give you control over audience definitions when Google’s predefined segments do not match your specific market. Instead of choosing from Google’s catalog of in-market or affinity audiences, you define the behavioral profile yourself.

You build a Custom Audience using one or more of these signal types:

Signal Type	What You Enter	Google Matches Users Who
Keywords	Terms your audience searches	Have recently searched those terms on Google
URLs	Websites your audience visits	Browse similar content to those sites
Apps	Apps your audience uses	Have installed or actively use similar apps

Google does not target users of those specific URLs or apps — it uses them as signals to find users with similar behavioral profiles.

How It Works

Creating a Custom Audience in the 2026 Google Ads interface follows this process:

1. Navigate to Tools > Shared library > Audience manager
2. Click “Custom segments” and create a new segment
3. Add signals — enter 10-15 keywords, 3-5 URLs, and relevant apps that define your ideal customer
4. Google builds the audience — using the signals to find users across its network who match the profile
5. Apply to campaigns — attach the custom audience to your Display, YouTube, or Performance Max campaigns

Google interprets your signals differently depending on the campaign type:

• Display and YouTube — signals are treated as interest/affinity indicators (broader reach)
• Performance Max — signals function as intent indicators and are used as audience signals for Google’s AI to optimize from

The audience size estimate shown during creation reflects the approximate reach. Aim for audiences between 100,000 and 10 million users for optimal delivery.

Practical Example

A B2B cybersecurity company wants to reach IT decision-makers evaluating endpoint security solutions. No single predefined In-Market Audience segment matches this specific niche.

They create a Custom Audience with:

Keywords: endpoint detection and response, enterprise antivirus comparison, MDR managed detection, SIEM vs EDR, zero trust security platform

URLs: gartner.com/reviews/market/endpoint-protection, crowdstrike.com, sentinelone.com, darkreading.com

Apps: Microsoft Defender, CrowdStrike Falcon

Campaign results after 60 days:

Metric	Custom Audience	Generic IT In-Market	Difference
Impressions	185,000	920,000	-80% (narrower)
Clicks	2,220	4,600	-52%
CTR	1.2%	0.5%	+140%
Conversions	44	32	+38%
CPA	$127	$359	-65%
Lead quality (SQL rate)	34%	11%	+209%

The Custom Audience generates fewer impressions but dramatically better engagement and conversion metrics because it reaches a precisely defined buyer profile.

Why It Matters

Custom Audiences are essential for advertisers in niche industries, B2B markets, or any vertical where Google’s predefined audience categories are too broad. They let you encode your market expertise into targeting — you know your buyers’ research patterns, competitor landscape, and information sources better than any predefined segment can capture.

The most effective approach is to combine Custom Audiences with broad campaign targeting and let Google’s AI optimize within your defined audience. Refresh the keywords and URLs periodically as industry trends evolve, and create multiple custom audiences to test different buyer profiles against each other. This gives you the precision of manual targeting with the optimization power of Google’s automated bidding.