Demand
Demand bidders are the SSPs and exchanges that compete for your inventory through header bidding. Configure them under Demand → Prebid in the main sidebar.
How it works
More bidders competing generally means higher clearing prices — but also more latency and more operational surface to manage.
Why demand matters
| Fewer bidders (2–3) | More bidders (5–10) | |
|---|---|---|
| Competition | Low | High |
| CPM | Lower | Higher |
| Fill rate | May have gaps | Better coverage |
| Latency | Faster | Slightly slower |
Sweet spot for most publishers: 5–10 well-configured bidders.
Managing bidders
| Task | Where | Link |
|---|---|---|
| View bidders | Demand → Prebid | View bidders |
| Enable a bidder | Demand → Prebid | Enable a bidder |
| Configure a bidder | Demand → Prebid | Configure a bidder |
| Set auction timeout | Wrapper → Configs | — |
| Set floors | On the ad slot, on a demand seat (per-partner), or globally in Wrapper → Configs | Floor concepts |
Auction timeout is a wrapper-level setting (Wrapper → Configs). Floors have three levels — global (Wrapper → Configs), per-slot (the slot's Auction tab), and per-demand-seat (on the seat under Demand → Prebid). There is no separate "Demand → Floors" or "Demand → Settings" page — earlier docs that referenced those paths were wrong.
Bidder types
SSPs (supply-side platforms)
Connect you to many advertisers at once: Rubicon / Magnite, PubMatic, Index Exchange, and similar.
Exchanges
Programmatic marketplaces: OpenX, Sovrn, Xandr (AppNexus).
Direct / private marketplaces
Bidders configured for specific advertiser relationships or PMP deals — often with unique inventory requirements.
Key settings per bidder
| Setting | What it controls | Typical value |
|---|---|---|
| Enabled | Bidder participates in auctions | On |
| Seat / account ID | Your bidder-side identifier | Per SSP |
| Slots enabled | Which ad slots this bidder can bid on | All, or a subset |
| Params | Bidder-specific parameters | Per SSP docs |
Wrapper-level settings like Auction Timeout and the global floor live in Wrapper → Configs, not per-bidder. (Currency is set on your account; price granularity is a GAM price-bucket setting on the GAM account — neither is a wrapper Config field.)
Quick actions with the AI Assistant
Many demand tasks — enabling or disabling a bidder, adjusting the wrapper timeout, checking your best-performing bidder — can be done by asking the AI Assistant in plain language. It proposes the change and applies it with your approval. See the AI Assistant guide.
Best practices
Do
- Enable 5–10 well-configured bidders
- Set a reasonable timeout (1000–1500 ms)
- Use floors to filter low-quality demand — once you have baseline fill-rate data
- Monitor bidder performance weekly
Don't
- Add bidders without checking latency impact
- Set timeouts so short that you cut off valid bids
- Set timeouts so long that CWV suffers
- Ignore bidders with chronically low bid rates