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TLS / STARTTLS
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TLS / STARTTLS
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All 24
TLS / STARTTLS
Check STARTTLS support, the negotiated protocol, certificate and cipher strength.
smtp › STARTTLS
Mail server or domain
Run check
Tip — type a command to jump tools:
tls:
mail.stripe.com
Try one
stripe.com
TLS 1.3
mailblast.biz
cleartext
What this checks
01
Connecting on port 25
02
Negotiating STARTTLS
03
Reading protocol version
04
Inspecting certificate
05
Enumerating ciphers