Meta Business Help Centre

Understand fluctuations in ad performance

Follow these general guidelines when interpreting ad performance:

Look at overall results. If you're using Meta Advantage campaign budget (formerly known as campaign budget optimisation), this means that you should analyse results for your campaign as a whole. If you're using ad set budgets, analyse results for your overall ad set.
Be careful when using specific result breakdowns. For example, if you break down the results of your ad set by hour, you may see performance oscillations that average out over time. Try using result breakdowns at the campaign level over the course of a full week. You can also try viewing results with no breakdowns at all to understand the overall performance of your campaign.
Remember that it's usually normal to see some fluctuations in spend. For example, daily budgets are an average over the course of a week, and may fluctuate up to 25% above your budget on some days and less on others. Also, there may be some hours of the day where we spend more or less depending on available opportunities. If you use a lifetime budget, you're telling us how much you're willing to spend over the entire run-time of your campaign or ad set. We may spend more on days when better opportunities are available, less on days with fewer opportunities. Note: If you schedule your ad set to run on a specific day and time, it can also affect how your overall budget is spent.
Focus on the optimisation event that you chose for your ad set. For example, if you've optimised your ad set for conversions, looking at the cost per thousand impressions (CPM) may not be a good indicator of performance. This is because the system may go after impressions with a higher cost, if that's how we can achieve lower conversion prices. Remember that the optimisation event is the outcome that our system will bid on in the ad auction, and can be different from your campaign objective. Learn how to customise your columns in Meta Ads Manager to see the cost of your chosen optimisation event.

Frequently asked questions

How do I know if my campaign is performing well?

Analyse performance over at least a full week to help understand whether you're getting a relatively steady amount of results. Remember that some variation in delivery is normal (for example, you may see more results in the afternoon and less at night). Try to resolve errors or warnings in the Delivery column (for your campaign, ad sets or ads). If you think you're seeing more than this normal variation, learn how to troubleshoot ad delivery.

Why are my campaign prices increasing over time?

The delivery system seeks the highest volume opportunities first. When those lower cost opportunities run out, the system may move on to more expensive options, depending on your bid strategy. This means you may see costs increase over the schedule of your campaign or ad set. Sometimes, constrained delivery can increase your average cost per result. Learn more about why your costs might be high.

Why is my cost per result exceeding my cost per result goal or bid cap?

A cost per result goal is an average amount that we try to stay under, while dynamically bidding as high as needed to maximise results. Costs may exceed your cap, especially during the learning phase. Cost per result goal is an input in the ad auction that you can set before your campaign starts. Alternatively, the cost per result that you see in Ads Manager reporting is a calculated metric, based on the average cost of results once your campaign is running. As cost per result is an average, it's best to avoid restrictive time breakdowns when comparing cost per result to your cost cap per result goal. For example, you may have higher costs during a specific hour that average out over the rest of the day.
A bid cap tells Meta the maximum that you can bid in auctions. Costs may exceed your cap during the learning phase. A bid cap doesn't control the cost per result that you see in Ads Manager reporting. Instead, we'll set a maximum bid across auctions, rather than bid dynamically based on your cost or value goals.

Some of my ads appear to have a higher cost per result, but they're getting more impressions than other ads with a lower cost per result.

If you break down the results of a specific ad or ad set (for example, by hour), you may see that an ad with an apparently higher cost per result is getting more impressions. However, you won't see the additional context of what optimisation events were available and how that changed over time. In reality, the ad that seems to have a higher cost per result may actually be getting you the most cost-effective optimisation events for that time period. This understandable misinterpretation is called the "breakdown effect". Learn more about the breakdown effect.

As a best practice, you should analyse results at the campaign level (if you're using Advantage campaign budget) or the ad set level (if you're using ad set budgets).

One of my placements appears to have a higher cost per result, but it's getting more impressions than placements with a lower cost per result.

If you break down the results of a specific ad or ad set (for example, by hour), you may see that a placement with an apparently higher cost per result is getting more impressions. However, you won't see the additional context of what optimisation events were available and how that changed over time. In reality, the placement that seems to have a higher cost per result may actually be getting you the most cost-effective optimisation events for that time period. This understandable misinterpretation is called the "breakdown effect". Learn more about the breakdown effect.

If you have specific requirements for certain placements, you may want to consider creating separate ad sets for each placement and using ad set budgets instead of Advantage campaign budget. Learn more about how to analyse results when you use Advantage+ placements with the highest volume bid strategy.

My ads seem to be delivering too fast or too slow in relation to their schedule.

If you think you're seeing more than normal performance fluctuation, check whether:

Your ad sets are in the learning phase. Ad performance is typically less stable during the learning phase. In Ads Manager, the Delivery column reads "Learning" when an ad set is in the learning phase.
Settings within your campaign, ad set or ad are constraining delivery. Constrained delivery can cause results to slow down or even stop entirely. Learn what to do if your campaign slowed down or stopped, or if your ad set slowed down or stopped.
Your budget or schedule was changed near the end of the day. If you change your budget or schedule near the end of the day, the system may not have enough time to apply new settings. For example, if you decrease your daily budget from USD 200 to USD 100 at 17:00, the system may have spent over your new daily budget of USD 100 already. Or, it may not have enough time to adjust and slow down delivery.