Daily budget overspend calculator
Google Ads can spend up to twice your average daily budget on a single day, but no more than 30.4 times it in a month. Enter your budget to see what that means in money.
Why Google spends more than your daily budget
Google treats your daily budget as an average, not a limit. Searches rise and fall from day to day, so on busy days Google may spend up to 2× your average daily budget, and on quiet days less. Over a calendar month you won't be charged more than 30.4× your average daily budget (30.4 is the average number of days in a month). If Google delivers more than that, it credits the difference.
So a $50 daily budget can cost up to $100 on one day, and up to $1,520 in a month. Google's own explanation is in its help page on why daily costs can exceed your budget. Google notes that some campaign types handle budgets differently, so check itsspending limits page for yours.
When it matters
Over a month the total works out as promised. The trouble is the single day. If you set the budget to what you can afford each day, a double day can surprise you, especially early in the month or when cash is tight. A spike can also come from a cause you'd want to know about, such as a broad keyword suddenly matching more searches.
What you can do
- Budget from your worst day. If $100 is the most you're comfortable spending in one day, set an average daily budget of $50.
- Stop ads in hours that don't pay off. An ad schedule keeps ads off at times that never bring calls or sales.
- Watch spend daily. Automated rules in Google Ads can pause a campaign when its cost passes an amount, but they run on a schedule, so they can act late.
The full guide: Google Ads spent more than my daily budget.SpendCanary's daily monitoring alerts you when a day's spend is at least twice your usual daily spend; seewhy spend suddenly jumps. A hard daily spend cap is coming soon.