Google Ad Manager is the default for a reason. Across the top 10,000 US sites, Google accounts for 84% of all ad servers detected. It costs nothing until you cross the impression cap, and it hands you AdX demand on day one. Almost nobody starts anywhere else.
The reasons publishers start looking elsewhere are consistent. The free tier stops at 90 million monthly non-video impressions in the US, Canada, Australia and New Zealand, with a hard 800,000 monthly ceiling on video regardless of location. Customization is thin once you want anything beyond IAB-standard display. Serving is client-side and tag-based, which means load time costs and no revenue from ad-block users. And in April 2025 a federal judge ruled that Google illegally monopolized the publisher ad server and ad exchange markets, with the DOJ pushing for divestiture of AdX and, if needed, the rest of Ad Manager. A remedies decision is still pending.
This piece covers eight replacements, split by whether you sell web inventory or in-app inventory. It starts with something that sits in a different category entirely.
UndrAds is an add-on that runs on top of Google Ad Manager
A lot of migration decisions get made for the wrong reason. Revenue sags, the ad server takes the blame, and three months of engineering time goes into a switch. Then the same sag reappears on the new platform.
The reason it reappears is that a meaningful share of lost ad revenue has nothing to do with which auction runs. It comes from reaction time. A tag decays, eCPM slides, and the ad ops team learns about it four to six hours later during the next dashboard review. A placement earning $200 an hour loses $700 or more per incident, and the incident repeats several times a week. That is a bandwidth limit, not a capability limit, which is why hiring more ad ops people rarely fixes it either.
UndrAds connects to your existing Google Ad Manager setup through API access. It monitors key metrics continuously, catches a drop the moment it starts, and switches tags within the hour rather than after someone notices. Every action it takes shows up in real time in Slack or whichever channel you already use.
- No SDK
- No app changes
- No migration
- Runs alongside any platform below
That puts it in a useful position for two different readers. If you decide GAM is fine and the problem is execution speed, UndrAds closes the delay window without touching your stack. If you do migrate to one of the platforms below, it works the same way on the new platform, since reaction delay follows you across mediation and ad server changes. Either way, it is worth ruling out the timing problem before you commit to a replatform. More on the mechanics in our breakdown of how AI agents are changing ad operations.
Everything from here on is an Ad Manager replacement.
The alternatives at a glance
| Platform | Type | Best for | Pricing model |
|---|---|---|---|
| Kevel | Server-side ad serving APIs | Marketplaces, retail media, custom native ad products | Custom, usage-based |
| Equativ Ad Manager | Independent full stack (ad server, SSP, curation) | Mid-to-large publishers wanting a non-Google programmatic partner | Custom, revenue share |
| Microsoft Monetize | Enterprise SSP with built-in ad server | Publishers with large direct and managed sales operations | Custom |
| Broadstreet | Hosted ad server for niche publishers | Local news, digital magazines, direct sales teams | From roughly $299/month |
| Revive Adserver | Free open-source, self-hosted | Small publishers with engineering resources | Free, plus hosting cost |
| AppLovin MAX | In-app mediation | Mobile games and apps across mixed portfolios | Revenue share |
| Unity LevelPlay | In-app mediation | Unity-built games and studios inside the Unity stack | Revenue share |
Google Ad Manager alternatives for web publishers
1. Kevel
Kevel sells ad-serving infrastructure as APIs instead of a finished dashboard. You build the ad server you want on top of it, which is the path taken by marketplaces and retail media networks that need sponsored listings, custom native units, and their own advertiser-facing portals. Its client list includes Yelp, Ticketmaster, Edmunds, Mozilla and WeTransfer.
The structural difference from GAM is that ad calls are server-side. That matters for two reasons: page and app load times improve, and inventory stays monetizable for the roughly 30% of users running ad blockers who would otherwise see nothing from an on-page tag.
The cost is engineering. Kevel is a build, not a setup. If you have no developers to assign and you need something running this quarter, it is the wrong tool.
Best for: commerce platforms, marketplaces, and publishers building a first-party ad product.
2. Equativ Ad Manager
Equativ, previously Smart AdServer, is the largest independent alternative that gives you an ad server and an SSP under the same roof. Its 2024 merger with Sharethrough created an entity with more than 720 employees across 18 countries and over $200 million in net recurring revenue, and the two unified under the Equativ brand in June 2025.
For publishers whose objection to GAM is the conflict of interest baked into Google owning both the server and the exchange, Equativ is the closest like-for-like swap: display, video, CTV, native, plus curation tools and server-side ad insertion for advanced TV. The onboarding is a managed process rather than self-serve, so expect a sales conversation and a contract.
Best for: mid-to-large publishers who want scale and independence in the same platform.
3. Microsoft Monetize
Microsoft Monetize is the sell-side half of what used to be Xandr, and before that AppNexus. Microsoft shut down the Invest DSP on February 28, 2026, and that caused some confusion about the publisher side, so it is worth being precise: Monetize and Curate remain active and funded. Only the buy-side product went away.
As a platform it covers end-to-end setup of both advertiser and publisher information, inventory management, forecasting, and priority handling between direct and auction demand. Publishers running large managed-sales operations get the most out of it, since reselling and direct campaign optimization are first-class features rather than bolted on.
The tradeoff is the same one you were trying to escape: you are trading Google’s ownership of your stack for Microsoft’s. If your objection to GAM is philosophical rather than practical, weigh that carefully.
Best for: enterprise publishers with meaningful direct-sold volume.
4. Broadstreet
Broadstreet has narrowed its focus deliberately: local news sites, regional digital magazines, and publishers whose sales teams sell to businesses in their own city. The pitch is Ad Manager without the parts a ten-person newsroom will never use. Plans start around $299 per month.
The product reflects the audience. In-content mobile units, sponsored content tracking, automated campaign reports for advertisers, and an ad format library aimed at people who need to send a local restaurant a performance summary rather than model a yield curve.
It is a poor fit if programmatic revenue is your main line. Broadstreet is built around direct sales, and you will still need a separate path to exchange demand.
Best for: local publishers and digital magazines with a direct sales team.
5. Revive Adserver
Revive is free, open source, and self-hosted. You download the script, run it on your own infrastructure, and own the whole thing. For publishers who object to giving any vendor visibility into their inventory, that is a real answer.
It is also the highest-maintenance option on this list. There is no support team, only a community site, and the script is heavy enough that server costs climb as you scale. Patching, monitoring and uptime are your problem. The total cost stops being zero fairly quickly once you price in the engineering hours.
Best for: small publishers with in-house technical staff and strong data-ownership requirements.
Google Ad Manager alternatives for app and game studios
GAM does serve in-app inventory, and its Open Bidding feature lets exchanges like PubMatic, Index Exchange and OpenX compete server-side against Google’s own demand. For most mobile studios, though, the practical alternative is a mediation platform rather than another ad server. Two platforms dominate.
6. AppLovin MAX
MAX runs a hybrid auction where in-app bidders compete in real time and the winning bid is measured against waterfall instances. Bidding support covers Google, Meta Audience Network, Mintegral, Pangle and DT Exchange, with a long tail of waterfall-only integrations. AppLovin’s own exchange demand is deeply wired in and often takes a large share of winning bids.
One detail changes the calculus for growth-stage studios: AppLovin restricts its ROAS-optimized UA campaigns to publishers already running MAX mediation. If your user acquisition depends on those campaigns, your monetization choice is effectively made for you. Studios that find this uncomfortable are the ones most often shopping for MAX alternatives.
Best for: studios with mixed gaming and non-gaming portfolios where AppLovin demand performs well.
7. Unity LevelPlay
LevelPlay is ironSource Mediation, rebranded after Unity acquired ironSource in 2022, with the original ironSource bidder still underneath and Unity engineering layered on since. Demand partners include Unity Ads, Meta, AdMob and Ad Manager, AppLovin, Mintegral, Pangle and Liftoff.
The advantage is native Unity Editor integration and optimized access to Unity Ads demand, which matters if your game is built in Unity and Unity Ads is already a meaningful revenue line. Auction mechanics between LevelPlay and MAX are close enough in 2026 that the deciding factor is usually which platform’s proprietary demand performs better in your geos and genres.
Best for: Unity-built games, especially those already leaning on Unity Ads.
If you are earlier in the evaluation, our roundups of AdMob alternatives and in-game advertising companies cover the demand side in more depth.
How to choose
Work backwards from where your revenue actually comes from.
If most of your money is direct-sold: Broadstreet. You are paying GAM’s complexity tax for programmatic features you barely touch.
If most of your money is programmatic and your objection is Google’s dual role: Equativ or Microsoft Monetize. Both give you an ad server plus exchange access without Google on both sides of the auction.
If you are building an ad product rather than selling ad space: Kevel. Sponsored listings, retail media and custom native units are what it exists for.
If you have engineers and a hard data-ownership rule: Revive.
If your inventory is in-app: MAX or LevelPlay, decided by which demand source already performs for you, not by feature checklists.
If your revenue looks fine on paper but keeps leaking: check reaction time before you migrate anything. A four-hour gap between a performance drop and a tag switch costs the same money on every platform on this list.
One more thing worth doing before any migration: audit your header bidding setup. A lot of what gets blamed on the ad server traces back to wrapper misconfiguration and demand partner bloat. If you are newer to the mechanics, start with how header bidding actually works.
FAQ
Is Google Ad Manager actually free?
Up to a point. The free version covers 90 million monthly non-video impressions in the US, Canada, Australia and New Zealand, 200 million in supported European and Asian countries, and 150 million elsewhere, with a flat 800,000 monthly video impression limit regardless of location. Cross those thresholds and Google requires a paid contract, which is the point most publishers get pushed toward Ad Manager 360. A full walkthrough of the platform is in our guide to what Google Ad Manager is and how it works.
Will the antitrust case force me to change ad servers?
Nothing has been ordered yet. Judge Brinkema found Google liable in April 2025 and heard remedies arguments through late 2025, but she indicated the decision would come later and that any ruling will be appealed. Plan for a multi-year timeline. What the case does justify is having a tested fallback rather than an untested dependency.
Can I run more than one ad server at once?
Yes, and larger publishers commonly do. A frequent setup keeps GAM for programmatic and adds a lighter platform for direct-sold campaigns, sponsorships or house ads. Trafficking overhead goes up, so it is worth doing only when the direct-sold side is large enough to justify the second workflow.
How long does an ad server migration take?
Budget one to three months for a mid-sized web publisher, longer if you have complex line item hierarchies, forecasting rules or a large direct book to rebuild. The unglamorous part is not the technical cutover. It is rebuilding targeting logic and validating that reporting reconciles with what you were seeing before.
Do these alternatives give me AdX demand?
Generally no, or not directly. AdX access is tied to Google’s stack, and losing it is the single biggest revenue risk in leaving GAM. Independent servers connect you to their own exchanges and to Prebid demand instead, which is why publishers with heavy programmatic revenue often keep GAM in the mix even after adopting something else alongside it.
Does switching ad servers fix inconsistent revenue?
Only if the ad server was the cause. Migrations change which demand competes and how inventory is packaged. They do not change how quickly your team notices a decayed tag or a bidder timing out. If your revenue chart shows repeated drops that recover a few hours later, the pattern points at reaction time rather than auction mechanics.
Run a revenue leak audit before you migrate
Replatforming is expensive, slow, and often aimed at the wrong problem. Before you commit, find out how much you are losing to reaction delay on the setup you already have.
UndrAds runs a revenue leak audit on your existing Google Ad Manager account: how often performance drops, how long they last before anyone reacts, and what that window costs per month. No SDK, no app changes, no migration required to find out.
Get in touch with the UndrAds team to book the audit.
