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<?php $spfdata='v=spf1 mx 1.2.3.4 ~all'; if (preg_match('/^v=spf[a-z0-9~?\s.-]+$/i', $spfdata)){ echo "SPF seems to be ok"; } else { echo "Invalid syntax"; }
Output for 7.1.0 - 7.1.33, 7.2.0 - 7.2.34, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.34, 8.2.0 - 8.2.30, 8.3.0 - 8.3.30, 8.4.1 - 8.4.18, 8.5.0 - 8.5.3
SPF seems to be ok
preferences:
88.55 ms | 1669 KiB | 4 Q