There is no single calculation that will tell you the exact right price to charge advertisers that want to place ads on your blog. However, there are some rules of thumb and baseline calculations that you can use to get started. The real science of calculating the right online advertising rates comes through experimentation.
The truth is there are a lot of factors that affect the amount you should charge for online advertising on your blog.
The type of ad (image, video, text, and so on) can affect the price as well as placement and the payment structure (for example, pay-per-click vs. pay-per-impression vs. flat rate). For example, ads placed above the fold should cost more than ads below the fold, but the challenge is finding the right price to maximize earnings.
In other words, what is the right price to charge for each type of ad you'll publish on your blog and in each possible location where those ads can be displayed to visitors?
Blog Advertising Rate Calculation
The sweet spot for your ad pricing is the price that keeps ad space filled without undervaluing that space. A popular method for calculating blog advertising rates is to divide the number of daily visitors to your blog that could see the ad by ten. Your calculation would look like this:
Number of Daily Visitors Who Could See the Ad ÷ 10 = Flat 30-Day Advertising Rate for that Ad Space
It's important to understand that the value of your audience could affect ad pricing, too. For example, a blog with a highly targeted and desirable niche audience that advertisers want to connect with could demand a premium advertising rate from those advertisers.
Furthermore, your audience's propensity to click on ads can also affect advertising rates. For example, if your audience tends not to click on ads, you need to factor that into your pricing model.
Don't Undervalue or Overvalue Your Blog
It's important to price advertising space on your blog as close to that aforementioned sweet spot as possible.
However, until you identify what that sweet spot is, it can be easy to fall into the trap of undervaluing or overvaluing your blog.