Key Takeaways

Ever wondered why some publishers seem to make more money from the same amount of traffic? The answer might just be Prebid. Let's break down what this tech actually is, how it works, and why it matters for your monetization strategy.

What Is Prebid, Actually?

Prebid is an open-source technology that helps publishers implement header bidding. In plain english, it lets multiple ad buyers bid on your inventory at the same time, before your primary ad server (like Google Ad Manager) is even called. This creates a mini-auction in the "header" of your page.

Think of Prebid like hosting a silent auction instead of selling tickets one at a time to whoever shows up first. More competition usually means better prices.

The tech was originally developed by AppNexus (now part of Xanadu) in 2015, but is now managed by Prebid.org, a non-profit organization. This means it's not owned by any single adtech company, which is a big deal for transparency.

The Prebid Family: More Than Just JavaScript

When people say "Prebid," they're often talking about Prebid.js, which is the original and most widely-used component. But the Prebid ecosystem has grown to include:

Prebid.js

The JavaScript library that runs in the user's browser. It collects bids from your chosen demand partners before the page loads fully. This is whats called "client-side header bidding" because it happens on the users device.

Prebid Server

A server-side implementation that moves the bidding process to an external server. This is faster and lighter for users, but has some tradeoffs in terms of cookie matching and transparency. Playwire's implementation is a good example of server-side Prebid at scale.

Prebid Mobile

Specifically designed for mobile apps, where the header bidding concept works differently than on websites. According to Publift, mobile app publishers see average revenue increases of 30-40% after implementing Prebid Mobile.

Prebid Video

Specialized for video ad formats, supporting instream (pre-roll, mid-roll) and outstream video ads across various video players.

How Prebid Actually Works

Let's walk through what happens in those milliseconds between when someone loads your page and when they see an ad:

1. User visits your website

2. Prebid.js loads and sends bid requests to multiple SSPs/exchanges you've configured

3. These partners return their bids within a timeout period you set (usually 1000-2000ms)

4. Prebid collects all valid bids and passes the highest one(s) to your ad server

5. Your ad server compares these bids against its direct-sold campaigns and other demand

6. The winning ad creative displays on your page

The magic happens in Step 3-4. Instead of checking with partners one-by-one (the old "waterfall" method), Prebid asks everyone simultaneousy, which is both faster and more fair.

Why Publishers Actually Use Prebid

There are a few major reasons publishers implement Prebid:

1. Increased Revenue

By creating more competition for each impression, publishers typically see CPMs increase. According to Snigel, publishers using Prebid can see revenue increases of 20-50% compared to traditional waterfall setups.

2. Transparency

Since Prebid is open-source, you can see exactly how the auction works. There's no "black box" where mysterious algorithms decide who wins.

3. Control

Publishers decide which demand partners to include, what timeouts to set, and how to configure price floors. You're in charge of your own setup.

4. No Vendor Lock-in

Because it's open-source, you're not tied to a single technology provider's solution. Don't like how a partner is performing? Remove them from your Prebid config.

The Challenges of Using Prebid

It's not all sunshine and rainbows, though. Prebid comes with some challenges:

• Technical complexity: Setting up and maintaining Prebid requires developer resources

• Page load considerations: A poorly implemented setup can slow down your site

• Operational overhead: More demand partners means more relationships to manage

• Ad quality concerns: More demand sources can sometimes lead to lower quality ads if not managed properly

Is Prebid Right For Your Site?

Prebid makes the most sense for publishers who:

• Have at least 500,000 monthly pageviews

• Have development resources available

• Want to increase competition for their inventory

• Are willing to invest time in optimization

If you're just starting out, you might be better off with a managed solution like Adnimation or similar partner who can handle the technical details for you.

Beyond the Basics: Next Steps

Once you understand what Prebid is, you might want to dig into:

1. Prebid adapters and which demand partners to work with

2. Price floor optimization strategies

3. Timeouts and how they affect revenue and user experience

4. Server-side vs. client-side implementation tradeoffs

The official Prebid.org documentation is a great resource for diving deeper into these topics.

Final Thoughts

Prebid has become the industry standard for header bidding because it works. It's transparent, effective, and gives publishers more control over their ad stack. But it's not a "set it and forget it" solution—it requires ongoing attention and optimization.

Remember, the ad tech landscape keeps changing, and staying informed about tools like Prebid is essential for maximizing your site's revenue potential.