Base and Max CPM
This guide explains the difference between the base and max CPM campaign settings and how to use them appropiately.
Base CPM vs. Max CPM: What's the Difference?
Base CPM is the starting point for all campaign bidding. It's the default CPM before any optimizations are applied. Automated bid modifiers then adjust it up or down based on your campaign goals and historical performance. These modifiers help the system respond to real time conditions, raising bids when higher CPMs are likely to improve results, or lowering them when you can maintain efficiency at a lower cost.
Max CPM acts as a safeguard. It sets the absolute upper limit your campaign can bid, regardless of what automated modifiers recommend. Even if performance algorithms suggest a higher CPM could drive stronger results, the system will never exceed your Max CPM. This gives you full control over cost ceilings while still allowing optimization within your preferred range.
For branding campaigns, Base CPM remains important. The system automatically adjusts bids within the allowed range to keep your campaign pacing correctly. If the campaign starts to underpace, the platform may temporarily increase the effective CPM, only up to the Max CPM, to maintain desired delivery and reach. This balance keeps branding campaigns on track while maintaining clear, predictable spending limits.