$ echo outlook.com | doas smtpctl spf walk
157.55.9.128/25
157.56.232.0/21
157.56.240.0/20
207.46.198.0/25
207.46.4.128/25
157.56.24.0/25
157.55.157.128/25
157.55.61.0/24
157.55.49.0/25
65.55.174.0/25
65.55.126.0/25
65.55.113.64/26
65.55.94.0/25
65.54.121.120/29
65.55.81.48/28
65.55.234.192/26
207.46.200.0/27
65.55.52.224/27
94.245.112.10/31
94.245.112.0/27
111.221.26.0/27
207.46.50.192/26
207.46.50.224
207.68.169.173/30
207.68.176.0/26
207.46.132.128/27
207.68.176.96/27
65.55.238.129/26
65.55.238.129/26
207.46.116.128/29
65.55.178.128/27
213.199.161.128/27
65.55.33.64/28
157.55.0.192/26
157.55.1.128/26
157.55.2.0/25
65.54.190.0/24
65.54.51.64/26
65.54.61.64/26
65.55.111.0/24
65.55.116.0/25
65.55.34.0/24
65.55.90.0/24
65.54.241.0/24
207.46.117.0/24
65.55.78.128/25
111.221.112.0/21
207.46.58.128/25
111.221.69.128/25
111.221.66.0/25
111.221.23.128/25
70.37.151.128/25
157.56.248.0/21
213.199.177.0/26
157.55.225.0/25
157.55.11.0/25
207.46.100.0/24
207.46.163.0/24
65.55.169.0/24
157.56.110.0/23
157.55.234.0/24
213.199.154.0/24
213.199.180.128/26
157.56.112.0/24
207.46.51.64/26
64.4.22.64/26
40.92.0.0/14
40.107.0.0/17
40.107.128.0/17
134.170.140.0/24
2001:489a:2202::/48
2a01:111:f400::/48
23.103.128.0/19
23.103.198.0/23
65.55.88.0/24
104.47.0.0/17
23.103.200.0/21
23.103.208.0/21
23.103.191.0/24
216.32.180.0/23
94.245.120.64/26