tools / Email

SPF validator

Walk a domain's SPF record and every include, and count the 10-lookup budget.

DNS lookups 6 of 10Issues 1Source published recordResolver Cloudflare 1.1.1.1Time 57 ms

v=spf1 include:_spf-a.microsoft.com include:_spf-b.microsoft.com include:_spf-ssg-a.msft.net include:_spf1-meo.microsoft.com -all

Mail from any other server fails SPF (-all).
6 of 10 allowed DNS lookups used.
_spf1-meo.microsoft.com: Record is 270 characters, over the 255-character TXT string limit. Split it into 2 strings.
No blocking problems found.

Include tree

microsoft.com · 2 ms

include:_spf-a.microsoft.com pass if _spf-a.microsoft.com passes · lookup 1/10
- _spf-a.microsoft.com · 14 ms
  - ip4:216.99.5.67 pass for 216.99.5.67
  - ip4:216.99.5.68 pass for 216.99.5.68
  - ip4:202.177.148.100 pass for 202.177.148.100
  - ip4:203.122.32.250 pass for 203.122.32.250
  - ip4:202.177.148.110 pass for 202.177.148.110
  - ip4:213.199.128.139 pass for 213.199.128.139
  - ip4:213.199.128.145 pass for 213.199.128.145
  - ip4:207.46.50.72 pass for 207.46.50.72
  - ip4:207.46.50.82 pass for 207.46.50.82
  - ip4:65.55.42.224/28 pass for 65.55.42.224/28
  - include:spf.protection.outlook.com pass if spf.protection.outlook.com passes · lookup 2/10
    - spf.protection.outlook.com · 1 ms
      - ip4:40.92.0.0/15 pass for 40.92.0.0/15
      - ip4:40.107.0.0/16 pass for 40.107.0.0/16
      - ip4:52.100.0.0/15 pass for 52.100.0.0/15
      - ip4:52.102.0.0/16 pass for 52.102.0.0/16
      - ip4:52.103.0.0/17 pass for 52.103.0.0/17
      - ip4:104.47.0.0/17 pass for 104.47.0.0/17
      - ip6:2a01:111:f400::/48 pass for 2a01:111:f400::/48
      - ip6:2a01:111:f403::/49 pass for 2a01:111:f403::/49
      - ip6:2a01:111:f403:8000::/51 pass for 2a01:111:f403:8000::/51
      - ip6:2a01:111:f403:c000::/51 pass for 2a01:111:f403:c000::/51
      - ip6:2a01:111:f403:f000::/52 pass for 2a01:111:f403:f000::/52
      - -all everything else: fail
  - ~all everything else: softfail
include:_spf-b.microsoft.com pass if _spf-b.microsoft.com passes · lookup 3/10
- _spf-b.microsoft.com · 13 ms
  - include:_spf-mdm.microsoft.com pass if _spf-mdm.microsoft.com passes · lookup 4/10
    - _spf-mdm.microsoft.com · 13 ms
      - ip4:134.170.113.0/26 pass for 134.170.113.0/26
      - ip4:131.253.30.0/24 pass for 131.253.30.0/24
      - ip4:157.56.120.128/26 pass for 157.56.120.128/26
      - ip4:134.170.174.0/24 pass for 134.170.174.0/24
      - ip4:134.170.141.64/26 pass for 134.170.141.64/26
      - ip4:134.170.143.0/24 pass for 134.170.143.0/24
      - ip4:157.58.249.3 pass for 157.58.249.3
      - ip4:65.55.29.77 pass for 65.55.29.77
      - ip4:131.253.121.0/26 pass for 131.253.121.0/26
      - -all everything else: fail
  - ip4:207.46.22.35 pass for 207.46.22.35
  - ip4:207.46.22.98/29 pass for 207.46.22.98/29
  - ip4:217.77.141.52 pass for 217.77.141.52
  - ip4:217.77.141.59 pass for 217.77.141.59
  - ip4:203.32.4.25 pass for 203.32.4.25
  - ip4:23.103.224.0/19 pass for 23.103.224.0/19
  - ip4:206.191.224.0/19 pass for 206.191.224.0/19
  - ip4:65.52.80.137/32 pass for 65.52.80.137/32
  - ~all everything else: softfail
include:_spf-ssg-a.msft.net pass if _spf-ssg-a.msft.net passes · lookup 5/10
- _spf-ssg-a.msft.net · 2 ms
  - ip4:104.44.112.128/25 pass for 104.44.112.128/25
  - ip4:134.170.27.8 pass for 134.170.27.8
  - ip4:157.58.30.128/25 pass for 157.58.30.128/25
  - ip4:20.63.210.192/28 pass for 20.63.210.192/28
  - ip4:20.94.180.64/28 pass for 20.94.180.64/28
  - ip4:40.112.65.63 pass for 40.112.65.63
  - ip4:52.185.106.240/28 pass for 52.185.106.240/28
  - ip4:52.234.172.96/28 pass for 52.234.172.96/28
  - ip4:52.236.28.240/28 pass for 52.236.28.240/28
  - ip4:66.119.150.192/26 pass for 66.119.150.192/26
  - ~all everything else: softfail
include:_spf1-meo.microsoft.com pass if _spf1-meo.microsoft.com passes · lookup 6/10
- _spf1-meo.microsoft.com · 12 ms
  - ip4:52.235.253.128 pass for 52.235.253.128
  - ip4:20.141.10.196 pass for 20.141.10.196
  - ip4:20.118.139.208/30 pass for 20.118.139.208/30
  - ip4:20.98.194.68/30 pass for 20.98.194.68/30
  - ip4:20.83.222.104/30 pass for 20.83.222.104/30
  - ip4:20.88.157.184/30 pass for 20.88.157.184/30
  - ip4:20.59.80.4/30 pass for 20.59.80.4/30
  - ip4:20.51.6.32/30 pass for 20.51.6.32/30
  - ip4:20.97.34.220/30 pass for 20.97.34.220/30
  - ip4:20.107.239.64/30 pass for 20.107.239.64/30
  - ip4:20.105.209.76/30 pass for 20.105.209.76/30
  - ip4:20.98.148.156/30 pass for 20.98.148.156/30
  - ip4:20.69.8.108/30 pass for 20.69.8.108/30
  - ~all everything else: softfail
-all everything else: fail

JSON: /spf-validator/api?domain=microsoft.com