Internet traffic is like an ocean: sometimes the waves are not alarming, sometimes the waves are choppy. If your ad doesn’t get enough impressions due to low traffic, we’ll show your ad more frequently when traffic is high, in order to make up for the previous loss.
It is for this reason that we allow up to 20% of the ad’s clicks to float within a day, without having to strictly enforce your daily budget. This situation is calledOverdelivery. This approach is beneficial to you: if the end result is that we have displayed your ads too much, and your advertising costs have exceeded the maximum allowed (that is, your daily budget multiplied by the number of days in the billing cycle The amount you get), then we will provide you with a refund amount for the extra cost.
As mentioned above, your daily advertising costs may be slightly higher than the daily budget, or may be slightly lower than the daily budget. You don’t have to worry about this situation. In a one-month billing cycle, the system will never charge you more than a fixed value, which is your daily budget multiplied by 30.4 days.
Let's take a closer look at this number.
The average number of days per month is approximately 30.4 (365 days a year/12 months = 30.417). Google multiplies your daily budget by this number, and the result is your advertising budget for the month.
Fluctuations in network traffic will cause your daily expenses to change up and down; but by the end of the month, you will find that despite these unpredictable fluctuations, your fees will exactly match the expected amount.
The amount of ads delivered can sometimes exceed your monthly budget. In this case, we will refund the overdelivery credit back to your account. To find out if you received a refund for overdelivery, please follow these steps: