CTR: how's it calculated?

Is it by visitors or by impressions?

[uhwebs]

I see people saying they have a CTR of, say, 5-10%.
I'm wondering how you calculate CTR. Is it clicks per impressions, or is it based on visitors?

If I use google's impressions, I have a CTR of around 3-3.5%. But if I calculate it off visitors, it's more like 7-8%.
It seems like it makes more sense to calculate off visitors... then you know what % of you visitors are clicking.

[Meike]

But what if your visitors click more than one ad? That will skew your percentages.

[uhwebs]

Hmmm, that's true. But I guess I was trying to figure out a way to calculate how much I make per visitor (but it changes ever day).

[david_uk]

If you want to use a spreadsheet to calculate it, you simply use the adsense data and the formula (clicks/impressions)*100 or use the % format in Excel.

I use this forumla and it comes up with the same numbers as Google. Unless a different way of calculationg it has some meaning or purpose to you, stick with Google's figures.

If you want to calculate earnings per visitor, then get the visitor numbers from your weblogs and divide earnings (from Google) / visitors (from weblogs)

[AdSenseAdvisor]

For the answer to this question, check out the AdSense Glossary:

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