Quick answer: An ad server is the software that decides which ad to show in each slot on your site or app, delivers it and records the result. As of October 2026, the main options for publishers include Google Ad Manager (formerly DoubleClick for Publishers), Equativ (formerly Smart AdServer), AdButler, Kevel (formerly Adzerk), Broadstreet, Epom and the free, open-source Revive Adserver. Several names from our 2020 list, including Verizon Media’s ad server, AerServ, AdGear and RhythmOne, have closed or been absorbed into other companies.
As a website builds an audience, Google AdSense alone often stops being enough. Publishers who start selling ads directly to sponsors, or who want several ad networks to compete for each impression, need an ad server to control their inventory: which campaign runs where, how often, at what priority, and how each one performed.
Ad server, ad network or SSP?
These terms are often mixed up, and our original list mixed them too:
- Ad server: software you control that stores your campaigns and decides which ad fills each slot. Example: Google Ad Manager.
- Ad network: a company that sells advertisers’ ads on your site and shares the revenue. Example: Google AdSense.
- Supply-side platform (SSP): technology that sells your ad space through real-time auctions to many buyers at once. Examples: OpenX, Media.net.
A typical set-up uses an ad server to manage direct deals and then lets ad networks and SSPs compete for the remaining impressions. The numbered list below covers ad servers. Networks and SSPs from our earlier list appear in a separate section.
How to choose an ad server
- Direct sales or programmatic: if you mostly sell sponsorships to local or niche advertisers, a simple direct-sales ad manager may be enough. If you want programmatic demand, check which exchanges and header-bidding set-ups the server supports.
- Formats and channels: display, video (VAST), native, mobile apps, connected TV (CTV) or digital out-of-home (DOOH).
- Hosted or self-hosted: a hosted service is easier; a self-hosted server gives full control but needs technical staff.
- Reporting for advertisers: direct advertisers expect clear impression and click reports, ideally through a portal they can log in to.
- Retail media: marketplaces and online shops that sell ad space on their own sites need sponsored-product formats, which some servers now specialise in.
- Cost: pricing is often based on impressions served. Compare at your real monthly volume.
Ad servers compared
| Ad server | Best for | Pricing model | Channels |
|---|---|---|---|
| Google Ad Manager | Large publishers with significant direct sales | Paid account required above an impression threshold; Ad Manager 360 is a paid tier | Web, apps, video |
| Equativ | Publishers and broadcasters, especially CTV | Check vendor | CTV, web, retail media |
| AdButler | Media networks and retail media | Check vendor | Display, video, email, mobile, native, CTV/OOH |
| Kevel | Retail media and marketplaces building their own ad platform | Check vendor | API-based, on-site ads |
| Broadstreet | Local news, magazines and B2B publishers selling direct | Check vendor | Web (check vendor for other formats) |
| Epom | Ad networks and publishers wanting a white-label server | Published pricing page | Display, video, native, rich media, mobile, DOOH |
| Revive Adserver | Technical teams wanting a free, self-hosted server | Free open source; hosted edition available | Web |
The 7 ad servers in detail
1. Google Ad Manager (formerly DoubleClick for Publishers)
DoubleClick for Publishers (DFP) and the DoubleClick Ad Exchange were combined and renamed Google Ad Manager in 2018. Our original list counted DFP and Google Ad Manager as two products; they are the same platform, so they now share one entry. Google describes Ad Manager as an ad management platform for large publishers with significant direct sales. It can let several ad exchanges and networks, including AdSense and third-party networks, compete for your inventory. Google’s help centre says publishers must move to a paid account once they pass an impression threshold, and Ad Manager 360 is the paid tier with direct Google support and extra features.
2. Equativ (formerly Smart AdServer)
Smart AdServer now operates as Equativ, and smartadserver.com redirects to equativ.com. Equativ calls itself an end-to-end media platform. For publishers it lists monetisation through its SSP, a CTV ad server and retail media tools. It suits broadcasters and publishers who want direct and programmatic campaigns managed together, particularly on connected TV. The original article’s claim that it was “the most feature-rich option in the market” has been removed, as it was not attributed to any independent comparison.
3. AdButler
AdButler describes itself as a platform for modern media networks. It offers ad servers for display, video, email, mobile, native and CTV/out-of-home, white-label self-service portals for advertisers, and tools for retail and commerce media networks. It has moved from serving mainly small publishers towards businesses that run their own advertising networks, but it still covers classic publisher ad serving with campaign management and reporting.
4. Kevel (formerly Adzerk)
Adzerk is now called Kevel, and adzerk.com redirects to kevel.com. As the original article noted, Kevel is API-first: companies use its ad server API to build their own ad platform rather than adopting a ready-made interface. Its site now focuses on retail media, marketplaces, fintech, travel brands and delivery apps, with an AI console, audience tools and an ad server.
5. Broadstreet
Broadstreet calls itself the ad manager built for small publishers: local news sites, city and regional magazines, industry journals and other publishers that sell ads directly to their own clients. That focus is unchanged from our original description. If most of your revenue comes from local sponsors rather than programmatic networks, a direct-sales tool like Broadstreet is simpler than an enterprise ad server.
6. Epom Ad Server
Epom offers a cross-channel ad server for ad networks, publishers and advertisers, with separate display, video, native, rich media, mobile and DOOH ad server products. Its site lists white-labelling, an ad server API and a VAST inspector, and it publishes a pricing page. A white-label ad server lets an ad network run the platform under its own brand.
7. Revive Adserver (new addition)
Revive Adserver is a free, open-source ad server that you install on your own web server. It manages advertisers, campaigns, banners and zones, and reports on statistics. A paid hosted edition is available for those who do not want to run it themselves. It is a practical choice for technically capable small publishers who sell ads directly and want no per-impression fees, but you are responsible for updates and security.
Ad networks and SSPs from our earlier list
These three are still active but are monetisation partners rather than ad servers, so they are not counted in the list above:
- Google AdSense: Google’s ad network for publishers. It fills ad slots automatically with Google advertisers’ ads and is the usual starting point for small sites. AdSense can also compete for inventory inside Google Ad Manager.
- OpenX: now describes itself as a supply-side platform, with products for curation, yield management and a real-time exchange. It no longer markets a stand-alone ad server.
- Media.net: now calls itself a sell-side platform, offering monetisation solutions and exclusive demand to publishers. The original article’s claim that it was the “second largest” contextual platform has been removed, as we could not verify it.
What happened to the other names on our original list
- Verizon Media ad server: Verizon Media (then Oath) announced in 2019 that it would close the Oath Ad Platforms ad server in 2020. In 2021 Verizon sold a 90% stake in its media business to Apollo Global Management, and the business now trades as Yahoo; and Yahoo announced in 2023 that it would also shut down its SSP.
- Zedo: Discovery, Inc. acquired Zedo in December 2021; it later became part of Warner Bros. Discovery. Zedo’s website did not respond when we checked in October 2026, so we do not list it as an available product.
- AerServ: acquired by InMobi in January 2018. Its website no longer responds.
- AdGear: bought by Samsung in 2016, as the original article reported. adgear.com now redirects to Samsung Ads.
- RhythmOne: rhythmone.com now redirects to Nexxen, an advertising technology company with a DSP and SSP.
Frequently asked questions
Do I need an ad server if I use AdSense?
Not at first. AdSense places ads automatically. An ad server becomes useful when you sell ads directly to advertisers, run house ads, or want several networks to compete for the same slots.
Is Google Ad Manager free?
Google Ad Manager has a standard account and a paid Ad Manager 360 tier. Google’s help centre says publishers must sign up for a paid account once they reach a specific impression threshold. Check the current threshold and terms with Google.
What is the difference between first-party and third-party ad servers?
Publishers use a first-party ad server to manage the ads on their own sites. Advertisers and agencies use third-party ad servers to deliver and track the same campaign across many publishers. This article covers publisher-side ad servers.
Is there a free ad server?
Yes. Revive Adserver is free and open source, though you need your own hosting and the skills to maintain it.
For other ways to earn from a website, see our guides to affiliate marketing networks and platforms and how media companies use affiliate marketing.
Product details were checked in October 2026 against each vendor’s website, Google’s Ad Manager and AdSense help pages, and published reports of the Verizon Media, Yahoo, Zedo and AerServ changes. Ad tech changes quickly, so confirm features and pricing with the vendor before you sign up.
