SPF

Sender Policy Framework (SPF) is another authentication tool to prevent spamming and spoofing. SPF allows senders to define which IP's are allowed to send email for a particular domain.

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SPF Adoption Over Time

Apr 2024: 99.96%
Mar 2024: 99.98%
Feb 2024: 99.98%
Jan 2024: 99.97%
Dec 2023: 99.81%
Nov 2023: 99.85%
Oct 2023: 99.8%
Sept 2023: 99.65%
Aug 2023: 99.11%
July 2023: 98.57%
June 2023: 95.71%
May 2023: 98.16%
Apr 2023: 97.51%
Mar 2023: 94.38%
Feb 2023: 92.33%
Jan 2023: 93.81%
Dec 2022: 97.56%
Nov 2022: 98.83%
Oct 2022: 99.17
Sept 2022: 99.21%
Aug 2022: 99.39%
July 2022: 99.31%
June 2022: 99.0%
May 2022: 98.96%
Apr 2022: 99.07%
Mar 2022: 98.85%
Feb 2022: 98.22%
Jan 2022: 98.21%
Dec 2021: 98.32%
Nov 2021: 98.47%
Oct 2021: 98.66%
Sept 2021: 96.43%
Aug 2021: 98.15%
July 2021: 97.74%
June 2021: 96.12%
May 2021: 98.13%
Apr 2021: 96.67%
Mar 2021: 95.52%
Feb 2021: 95.93%
Jan 2021: 97.05%
Dec 2020: 95.89%
Nov 2020: 93.07%
Oct 2020: 0%
Sep 2020: 0%
Aug 2020: 0%
Jul 2020: 0%
Jun 2020: 0%