How do I calculate the maximum cost per click?

Multiply the profit from one order by your website's conversion rate. For example, with a profit of 600 CZK per order and a conversion rate of 2%, the limit is 12 CZK per click. If you pay less than that per click, the advertising pays off; if you pay more, you're losing money.

What daily budget should I start with?

As a rough guide, one that covers at least 10 clicks a day. With an expected cost of 8 CZK per click, that's about 80 CZK a day. With fewer clicks, the campaign collects data too slowly and is hard to evaluate.

Is the budget set for the whole campaign or for ad groups?

In both Google Ads and Sklik, the daily budget is set at the campaign level. Ad groups hold the keywords and, in Sklik, also the bid per click. If you want to control spend for different products separately, split them into separate campaigns.

How to Set a PPC Budget: From Profit per Order to the Daily Limit

A PPC budget shouldn't be set by guesswork. Many businesses start by picking an arbitrary amount, for example 10,000 CZK a month, and hoping for the best. The right approach is the opposite: first you work out the most you can pay for a single click, and only then do you derive the budget from it. If you're not sure how PPC works, start with what PPC advertising is.

1. How much you can pay for one click

Before you set a budget, you need to know your break-even cost per click, the point up to which advertising still pays off.

The formula:

Max. cost per click = profit per order × website conversion rate

You get the profit per order as the order value × your margin.

Example:

Average order value: 2,000 CZK
Margin: 30%, so a profit of 600 CZK per order
Website conversion rate: 2% (2 out of 100 visitors buy)

Max. cost per click = 600 CZK × 0.02 = 12 CZK

The result: If you pay less than 12 CZK per click on average, the advertising pays off. At a higher price, you're losing money.

For services and lead-generation websites, use the profit per job instead of the order value, and leads instead of purchases. You get the conversion rate from your tracking, for example in Google Analytics 4. If you don't have it yet, the GA4 setup guide will help.

2. Where the budget is set: campaigns and ad groups

In advertising systems, the budget isn't a single number for the whole account.

Campaign level (daily budget):

This is where you set how much a campaign can spend per day. That applies to both Google Ads and Sklik.
If you want to manage spend for different products or services separately, split them into separate campaigns by priority. For example, your core services with a higher margin get a bigger share of the budget than add-on products.

Ad group level (keywords and bids):

Inside a campaign, you split keywords into ad groups by topic, for example "plumber Prague" and "emergency plumber".
An ad group has no budget of its own. In Sklik, you set the bid per click on it. In Google Ads, bids can be managed by an automated strategy, for example Maximize clicks with a maximum CPC bid limit.

3. How the systems handle your budget

Google Ads and the 30.4× rule:

On a busier day, Google Ads can spend up to twice your daily budget.
Over a calendar month, though, it won't charge you more than 30.4 times your average daily budget. 30.4 is the average number of days in a month.
If you change the budget during the month, the monthly cap is recalculated based on the new setting.

Sklik:

The lowest possible bid per click is 1 CZK excluding VAT.
Once the daily budget is used up, your ads stop showing for the day. If your budget runs out by mid-morning, you miss your afternoon customers. A higher budget, a lower bid or an ad schedule will help.

4. What budget to start with

Enough clicks to evaluate: As a rough guide, plan for at least 10 clicks a day (about 70 a week). With fewer, the campaign collects data slowly and the results are hard to evaluate.
Calculating the starting budget:

Minimum daily budget = expected cost per click × 10

With an expected cost of 8 CZK per click, that's about 80 CZK a day, or roughly 2,400 CZK a month.
Test length: Leave the settings unchanged for 2 to 4 weeks. Frequent changes to budgets and bids make evaluation harder and, with automated strategies, extend the learning phase.

If a campaign consistently doesn't spend the budget you've set, the problem usually lies somewhere other than the budget amount. The most common causes are covered in Google Ads Campaign Not Spending Budget. And how to split the budget between Google and Seznam is described in Google Ads or Sklik?

5. How MARLY handles this

MARLY saves you the manual calculations:

Calculated from your numbers: Based on your profit per order (or customer value) and the website type from the audit, MARLY calculates the maximum cost per click that still pays off for you. It derives the campaigns' daily budgets from your monthly budget.
The real market price: MARLY finds out what a click costs in Sklik and never sets the maximum cost per click below the market price, so that your ad actually shows. When the market is more expensive than pays off for you, it warns you.
Low-budget warning: If your budget covers fewer than 10 clicks a day, MARLY warns you and offers higher budget levels.
Unified control: You set the budgets and costs per click of your Google Ads and Sklik campaigns from one clear environment.

What MARLY can do and what we're working on is summed up in the article What Is MARLY and What Will It Do.