This post was most recently updated on November 6th, 2020
Prebid was created in early 2015, and large publishers started experimenting with it in 2016. Since then, header bidding has been one of the most frequently discussed in ad technology.
Around seven out of ten publishers have been using Prebid to boost their overall revenues or at least test it against conventional selling methods. The number of bidders, as well as which bidders you include in your auction, has both upsides and downsides. Because audiences vary from site to site, and thus the demand for such audiences varies from bidder to bidder, we’ve historically seen highest ROI on anywhere from 6 to 14 bidders implemented client-side in Prebid.
Let’s take a look at our list of top Prebid adapters for you to test and start implementing in 2019.
AppNexus is the pioneer in the development of open-source header bidding and provides access to a unique, diversified, and massive demand for publishers with its optimized Prebid adapter.
Medium to large publishers with impressions from all tiers can monetize their inventory well. The overall performance and in terms of bid rate and win rate is world-class.
Many other bidders using the AppNexus platform also bid through the AppNexus adapter, so virtually all Prebid builds will include the AppNexus adapter. Publishers using old versions of Prebid should upgrade to later versions with User Synch enabled so that they can take advantage of optimizations in bid handling that AppNexus has developed into their adapter.
Index Exchange takes the second position due to its top-notch demand and very significant share-of-voice among all bidders. It performs excellently on tier 1 geographical locations (US, UK, Australia, Canada). However, the numbers you would get for other geographic areas will also be very positive.
Rubicon offers unique demand, high CPMs, and good overall share of voice depending on the domain authenticity. As with many other adapters on this list, publishers can set up specific floors to optimize for better fill rate or higher CPMs. This means that you can adjust the adapter to get what you’re specifically looking for.
The OpenX adapter is backed up with significant unique and non-unique demand from top advertisers via private marketplaces and the OpenX Ad Exchange. Publishers can expect strong CPMs and overall higher revenues, while the fill rates and share of voice vary between different sites.
Because OpenX connects to so many other SSPs and DSPs, their share-of-voice is significantly higher than many other bidders. However, those gains often shrink when upstream buyers are buying through OpenX, and you start getting further down the list of all possible bidders to add. Regardless, even in advanced setups with numerous bidders, OpenX still adds significant value, and when in new or less advanced setups, they’re one of the highest ROI partners available.
Facebook started offering header bidding through its Audience Network (FAN) platform to select publishers in 2015, and has gradually opened up to more publishers since then.
The performance on mobile is above average due to distinct demand and higher winning bid percentages. That’s why it makes it to the top five bidders list. Under normal conditions, FAN only bids on mobile, and usually only if a user is logged into their Facebook account. Because of this, FAN can win significant impressions on users coming from Facebook as a traffic source.
Because of limitations on how FAN’s buy-side works, it is very hard for malicious advertisers to get through to your users with nefarious malvertising, making FAN’s creatives some of the highest quality available in the ecosystem, with minimal or no mobile redirects and popups.
Amazon’s header bidding technology started as an invite-only program for selected publishers. Amazon’s header bidding technology does not actually run inside Prebid and there is no Prebid adapter for it, but Amazon’s team has solid onboard documentation that helps your developers load Amazon’s bidding technology alongside Prebid’s auction without giving either an unfair advantage. As with all implementations, you’ll want to make sure Prebid and Amazon are loaded on the same timeout, and you’ll want to load them in an order that maximizes session RPM for your audience. Additionally, Amazon has started rolling out support for currencies other USD, so if your GAM account is in another currency, you’ll now be able to join the program.
Because Amazon doesn’t run inside Prebid, you cannot run them on standard Prebid line items. You’ll need a separate set of line items that they create. To do this, you’ll have to provide them with GAM API access so they can create these line items. Every publisher gets different hashed bid responses, so this setup allows them to obfuscate their bids from other bidders. While other bidders have tried to take this approach, Amazon has certainly proven their worth in the extra setup time and effort.
As the bulk of Amazon bids are from Amazon themselves, their ad quality is consistently among the highest quality, with minimal or no mobile redirects and popups.
For a small fee, Amazon also allows you to configure third party bidders to submit bids in a Server-to-Server pipeline through Amazon’s header bidding technology. This is worth considering, but it’s important to note that Server-to-Server never ended up living up to the hype it received. The highest session RPMs have consistently been found on publishers who deploy a significant amount of bidders on a significant amount of mobile traffic in a hybrid strategy that incorporates both Server-to-Server and header bidding.
Criteo focuses primarily on retargeting campaigns. As with many other bidders pushing first-price bids into GAM’s second-price auction, they had some difficulties in channel conflict. Those issues have largely been resolved, and Criteo has gained significant share-of-voice among publishers. Criteo is also one of the most common bidders being used by Alexa top 1000 sites.
CPX can be a great addition to your Prebid stack. The performance varies from domain to domain. However, if the demand matches your users, you would be amazed to see how it helps you sell a significant chunk of your worldwide inventory. CPX was originally an AppNexus bidding partner, so there’s no additional adapter to be added. They have since expanded to add an adapter for running off the AppNexus platform.
District M has consistently shown competitive CPMs, as well as a solid tech team to make sure everything is working smoothly. They will very likely add to fierce competition among your existing header bidding stack.
Like CPX, DistrictM has adapters for running both on and off the AppNexus platform.
Conversant makes it to the list of top ten Prebid adapters because of its capability to give a hard time to the rest of your header bidding stack.
It provides reasonable rates and the bid response time is good. If your domain is approved to run Conversant adapter demand, it is worth to add to your current stack and see how much difference it makes.
With header bidding, you can drastically increase your ad revenue. However, if you don’t have any experience or a development team to assist you, it can be a painful and expensive process getting started.
Here at MonetizeMore, we offer a turnkey header bidding solution called PubGuru Header Bidding that provides you with top performance, minimal management, and unified reporting – to name a few features.
If you’d like to implement any of these header bidding adapters on your site, but don’t know where to start, MonetizeMore can help through PubGuru Header Bidding! Sign up to get started today!
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