Quantcast Top 10k5,384 of 10,000
Quantcast Top 100k48,088 of 100,000
BuiltWith Top Million339,667 of 823,409
Entire Internet41,973,659 of 371,396,617
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The Sender Policy Framework is an open standard specifying a technical method to prevent sender address forgery.
Categories: Email Hosting Providers · Standard
This chart shows the amount of websites within the top 10k, 100k, and 1 million sites groups that are categorized as being in the specific vertical.
We know of 41,973,659 live websites using SPF in our records.
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