MFA sites (Made-for-Advertising) are websites created with a single purpose: generating ad revenue through traffic arbitrage. The operator buys cheap clicks from content recommendation widgets or social media clickbait, sends visitors to pages stuffed with ad placements, and pockets the difference between what they paid for the traffic and what they earned from the impressions.
The affiliate didn’t create useful content, build an audience, or run a legitimate campaign. They just spun up a website designed to extract maximum ad revenue from every visit. That’s an MFA site. And it’s one of the most persistent problems in programmatic advertising because these sites are specifically built to pass standard quality checks.
The scale is significant. The Association of National Advertisers (ANA) found that MFA sites accounted for 21% of all programmatic ad impressions and consumed 15% of total ad spend. Globally, MFA sites generate an estimated $13 billion in ad revenue per year. That’s money taken from advertisers who thought they were buying quality inventory.
How MFA Sites Work
The business model is straightforward, which is what makes it so scalable.
A fraudster registers dozens or hundreds of domains. They fill each site with AI-generated or syndicated content targeting trending search terms. The content doesn’t need to be good. It just needs to exist so the page can serve ads around it.
Next comes the traffic. MFA operators buy cheap clicks through content recommendation platforms, social media ads with sensationalized headlines, or paid search arbitrage. The clickbait works: “You won’t believe what this celebrity looks like now” or “Doctors hate this one trick” are the kinds of headlines that drive traffic to MFA pages.
Each page is packed with ad units. Banner ads, auto-refreshing placements, autoplay video, sticky ads, and slideshow formats that force visitors to click through multiple pages to read a single article. Every page load, every slide, every refresh generates new ad impressions.
The math is simple. If the operator pays $0.02 per click to acquire a visitor and earns $0.08 in ad revenue from that visit, they profit $0.06 per visitor. At 100,000 visits per day across a network of MFA domains, that’s $6,000 in daily profit. The barrier to entry is a few domain registrations, a WordPress template, and a ChatGPT subscription.
The Five Characteristics of MFA Sites
In September 2023, a coalition of four major trade organizations, the ANA, the 4A’s (American Association of Advertising Agencies), the World Federation of Advertisers (WFA), and the Incorporated Society of British Advertisers (ISBA), published an official definition. They identified five characteristics that MFA sites typically share.
1. High Ad-to-Content Ratio
MFA pages have ad density well above the internet average. The industry groups defined this as an ad-to-content ratio of 30% or higher on desktop. Some MFA pages stack six, eight, or ten ad units on a single page. Sticky ads, floating units, and interstitials are layered on top of thin content.
2. Auto-Refreshing Ad Placements
Banner ads that refresh every few seconds. Autoplay video units. Slideshow formats that force visitors to click through five or more pages to read one article, each page loading a fresh batch of ads. These tactics multiply the impressions per visit far beyond what a normal content site generates.
3. Paid Traffic Dependency
This is the most telling signal. MFA publishers have little to no organic audience. They don’t build loyal readerships. Almost all of their traffic comes from paid sources: content recommendation widgets, social media ads, and search arbitrage. If you look at an MFA site’s traffic breakdown, organic search and direct visits are minimal. Paid referrals dominate.
4. Generic or AI-Generated Content
The content exists to fill a page so that ads can be served around it. You’ll find syndicated articles copied across dozens of sites, outdated content that hasn’t been updated in years, and increasingly, bulk AI-generated articles with zero editorial oversight. The content only needs to look “real enough” to pass automated brand safety scans. That’s the only quality bar.
5. Templated, Low-Quality Design
MFA sites typically use the same handful of WordPress or custom templates. There’s no investment in user experience, navigation, or branding. Multiple MFA sites often share identical layouts because they’re run by the same operator using the same template across all their domains.
If a site checks two or three of these boxes, it’s likely an MFA operation.
Why Standard Quality Checks Miss MFA Sites
Here’s what makes MFA particularly dangerous: these sites are built to pass the exact checks advertisers rely on.
The ANA noted that MFA websites exhibit high measurability rates, good viewability rates, low levels of invalid traffic, and brand-safe environments. On paper, they look like quality inventory. The ads are technically viewable. The content isn’t flagged as unsafe. The traffic registers as valid.
There’s another trick that researchers discovered. Many MFA sites display a clean version of their pages when someone visits the URL directly, but load a completely different, ad-heavy version when traffic arrives through a paid referral link. So if an advertiser manually checks a placement by typing in the URL, the experience looks fine. The actual experience for visitors arriving through clickbait links is entirely different.
This is why traditional brand safety filters alone don’t work. MFA detection requires looking at behavioral signals, traffic source patterns, content quality, and ad density metrics that go beyond what standard viewability and IVT measurement covers.
The Real Cost to Advertisers
The financial impact goes beyond wasted media spend. MFA traffic creates problems across your entire marketing operation.
Inflated Campaign Metrics
MFA sites generate high impression counts and sometimes decent click-through rates. This inflates campaign metrics and makes it harder to identify which placements actually drive business results. If you optimize toward impressions or clicks rather than downstream conversions, MFA inventory will look like a top performer.
Budget Drain at Scale
An AdWeek study from November 2024 found that Performance Max campaigns had 40% of their traffic landing on MFA websites. For brands spending six or seven figures on programmatic, even 10-15% leaking to MFA inventory adds up to serious money spent on publishers who deliver zero engagement.
Polluted Analytics
MFA traffic contaminates your campaign data. The bounce rates, time-on-site, and engagement metrics from MFA visitors look nothing like real potential customers. If this data feeds into your attribution models or audience segments, you’re making optimization decisions based on junk signals.
Brand Association Risk
Your brand’s ads appearing next to AI-generated filler content surrounded by ten other ad units isn’t something any marketer wants. While MFA sites are generally “brand safe” in the narrow technical sense (no hate speech, violence, or adult content), the user experience is terrible. Consumers who see your ad on a cluttered, low-quality page aren’t forming positive associations with your brand.
How to Spot MFA Sites in Your Campaigns
Eliminating MFA inventory requires more than one tactic. MFA operators constantly adapt, so detection needs to be layered.
Audit your placements regularly. Don’t rely solely on automated quality checks. Review your top placements by spend and impressions. Visit the actual sites. Check how they look when accessed through a referral link, not just by typing the URL directly. Look at ad density, content quality, and whether the site has any real editorial identity.
Monitor traffic source patterns. Real publishers have diversified traffic sources: organic search, direct visits, social referrals, email newsletters. MFA sites depend almost entirely on paid traffic. If a placement shows 80%+ of its visitors coming from content recommendation widgets or paid social, investigate further.
Track post-click behavior. What happens after the impression or click? If a placement generates traffic but zero conversions, zero scroll depth, and sub-five-second session times, the quality is garbage regardless of whether the traffic is technically “valid.”
Build inclusion lists. Rather than trying to block every MFA site (new ones appear faster than you can blocklist them), curate a list of approved publishers. It limits reach slightly, but it’s the most reliable way to control inventory quality.
Check domain fundamentals. Use a domain scanner to check publisher domains before they enter your supply chain. Recently registered domains with no page authority, no organic traffic history, and no backlink profile are classic signals of throwaway MFA operations.
How AI Is Making the MFA Problem Worse
Generative AI has supercharged the MFA business model. Before tools like ChatGPT, creating content at scale required either paying writers or scraping existing articles (which was easier to detect). Now, MFA operators can generate thousands of unique articles per day at near-zero cost.
The content doesn’t need to be insightful. It just needs to exist, fill a page, and be different enough from other sites to avoid duplicate content penalties. AI handles that effortlessly.
This means the volume of MFA sites is growing faster than the industry can blocklist them. Detection needs to shift from reactive (blocking known MFA domains after they’ve already taken your money) to proactive (identifying MFA behavior patterns automatically, in real time).
How 24metrics Detects MFA Sites Automatically
This is where our AI-powered domain crawler comes in. Rather than relying on static blocklists that are always one step behind, our system actively analyzes publisher domains to classify MFA sites before they drain your budget.
The crawler visits and analyzes the actual pages your ads would appear on. It evaluates banner-to-content ratios, identifies excessive pop-unders and interstitials, detects auto-rotating and auto-refreshing ad placements, and flags pages where ad density crosses the thresholds defined by the ANA’s MFA criteria. This isn’t a surface-level URL check. The system renders the page and analyzes what a visitor actually experiences.
It also catches the infrastructure signals that MFA operators can’t hide. Recently registered domains with no page authority, no organic traffic history, and no backlink profile get flagged automatically. When someone spins up 50 new domains this week and fills them with AI-generated content, the crawler identifies the pattern before those domains make it into your ad supply chain.
For advertisers managing affiliate programs, this matters because affiliates may knowingly source traffic from MFA inventory to inflate their performance numbers and earn commissions on worthless conversions. Our system catches this at the click level, flagging traffic that originates from classified MFA domains before a payout is ever attributed.
You can also run a quick check yourself. Our free Domain Scanner lets you evaluate any publisher domain for reputation signals, registration history, and risk indicators. It’s a good starting point for manual audits before plugging into the full automated detection.
What Comes Next for MFA
The industry has made progress. Google has tightened parameters on its ad exchange programs. Major SSPs have introduced MFA filtering. The ANA’s awareness campaign pushed MFA from a niche issue to a boardroom-level concern, and spending on MFA sites dropped from 15% in late 2022 to roughly 4% by mid-2024 according to ANA’s follow-up data.
But the core incentive hasn’t changed. As long as programmatic advertising rewards impressions and clicks over actual business outcomes, there will be operators building websites designed to manufacture those signals at the lowest possible cost. And generative AI keeps lowering that cost every month.
For advertisers, the takeaway is clear: you can’t outsource quality control entirely to your DSP or ad exchange. You need impression screening and traffic analysis that looks beyond surface-level metrics. The brands that treat media quality as an ongoing operational practice, not a one-time setup, are the ones that keep their budgets intact.
Want to see how much of your ad spend goes to MFA inventory?
Talk to us and we’ll run a traffic analysis on your campaigns. The results tend to be eye-opening.
