Header Bidding Library
Back to librarySpot Duplicate Prebid Ad Unit Codes on a Template
Use ad-unit inspection to find duplicate codes before they create confusing runtime behavior.
Why this workflow matters
Teams use Prebid Ad Unit Inspector when they need to identify duplicated ad unit codes on a page or template before launch. Duplicate unit identifiers make debugging and reporting much harder once the page is live.
The search intent behind this topic is usually very specific: someone has a real debugging task in front of them and needs a practical workflow rather than a generic tool list. Prebid Ad Unit Inspector is the anchor tool for this page because it addresses the core evidence needed to move the issue forward.
How to investigate it
Open Prebid Ad Unit Inspector first and inspect the adUnits array, compare codes, and isolate repeated units before they become production ambiguity. Supporting tools such as Prebid Config Inspector and Prebid Timeout Risk Analyzer help once the first clue is visible.
The goal is not just to get an answer on screen. The goal is to produce a clean explanation that can be shared with engineering, ad ops, or an external partner without re-running the entire investigation from scratch.
What good output looks like
A useful result is a short list of duplicate units that the implementation team can fix immediately.
This is also where niche pages win SEO more often than broad phrases. People searching for this exact troubleshooting scenario want a focused answer tied to a real operational problem. A page like this converts that intent directly into a tool workflow instead of asking the reader to infer which utility to open.
Run the auction checks next
These tools help when the problem looks tied to config, timeout pressure, ad-unit setup, identity, or floors.
Prebid Ad Unit Inspector
Parse a real `adUnits` snippet and break it down into ad-unit codes, media types, sizes, bidder counts, and duplicate patterns. This is useful when a page looks overloaded, when bidders are attached to the wrong unit, or when teams need to understand the auction shape quickly before debugging runtime issues. It focuses on the ad-unit layer instead of the broader page shell.
Prebid Config Inspector
Inspect a Prebid `pbjs.setConfig` snippet and surface the auction settings that actually shape runtime behavior: bidder timeout, timeout buffer, consent modules, user sync, floors, S2S, and more. This tool is built for engineers and ad-ops teams who need a fast readout of whether a configuration is sane before they open devtools or live auction logs. Paste a real config block and get concrete findings instead of guessing which modules are active.
Prebid Timeout Risk Analyzer
Diagnose Prebid auction timeout risk from real config snippets, adUnits, and optional bidder timing notes. Instead of only guessing from fetched HTML, the tool inspects timeout settings, auction pressure, identity delay markers, and pasted bidder outcomes so teams get a more actionable first-pass readout of why bids may be missing the auction.
Keep moving through header bidding reviews
Use the next links when you need to move from one symptom into the wider auction picture without starting over.