Once an LEA has set up SPF, DMARC, DKIM it is a good idea to test each to make sure they are working as they are expected too.
dmarcian - DMARC Record Chekcer
dmarcian - SPF Surveyor
dmarcanalyzer - Validate SPF Record
ValiMail - DMARC and SPF Record Check
You can use one of the services below to send an email from your domain and have it checked for SPF, DMARC, and SPF. It is another way to get an evaluation of your email configuration.
Red Sift’s Investigate service shows DKIM, DMARC, and SPF results