Anthony McGrathHow the Google Ads budget calculator works
Your budget buys clicks, and a share of those clicks convert. Everything else follows from three numbers: the budget, the average cost per click (CPC) and the conversion rate.
Clicks = budget ÷ average CPC
Conversions = clicks × conversion rate
Cost per conversion = budget ÷ conversions
Budget needed = conversions wanted ÷ conversion rate × average CPC
Daily budget
Google Ads uses a daily budget and plans a month as 30.4 days. On a busy day it can spend up to twice your daily budget, but over the month it will not charge more than 30.4 times the daily figure.
Where to find your numbers
Use the average CPC and conversion rate from your own account if you have them. If you are new, Keyword Planner shows the top-of-page bid range for your keywords; the middle of that range is a fair starting CPC.
| Average CPC | Clicks | At 2% | At 4% | At 6% |
|---|---|---|---|---|
| £0.75 | 1,333 | 27 | 53 | 80 |
| £1.50 | 667 | 13 | 27 | 40 |
| £3.00 | 333 | 7 | 13 | 20 |
Questions
How much should I spend on Google Ads?
Start from the result you want. Divide the conversions you want by your conversion rate to get the clicks needed, then multiply by your average cost per click. Enough budget for at least 30 to 50 conversions a month lets Google’s smart bidding learn.
How do I work out a daily budget?
Divide your monthly budget by 30.4, the number of days Google uses for a month. £1,500 a month is about £49 a day.
What is a good conversion rate for Google Ads?
It depends on the market and the offer. Search campaigns often convert 2% to 6% of clicks. Use your own figure where you have one; small changes make a big difference to cost per conversion.
Why is my cost per conversion higher than the calculator shows?
Usually the real CPC is higher than planned, the conversion rate is lower, or conversions are not tracked properly. Check your tracking first: missing conversions make every number look worse.
Does this work for Performance Max and Shopping?
Yes, as a planning guide. Use the average CPC and conversion rate for that campaign type; Shopping often has lower CPCs and a different conversion rate from search.