How to know Adsense Fill Rate?

[MissMandy]

Im just wonder if anyone can tell me how to know Adsense fill rate? I cant see anywhere in their stats to show how much is the fill rate.

[Chris]

The only way is to compare your traffic stats through analytics with your ad stats.

Of course, that isn't a pure fill rate, because it would also include things like ad blockers. But that'll let you know certainly how many people aren't seeing ads.