How do I view email headers?
How to view email headers to debug deliverability issues.
Gmail Headers
- Open mail.google.com
- Open the email you wish to view the headers of.
- On the top right of the email next to reply, click the three dots (more) → Show original.
Source: https://support.google.com/mail/answer/29436
Outlook Web
- Open outlook.live.com
- Open the email you wish to view the headers of.
- On the top right of the email, click the three dots → View → View message source.
Outlook App
- Open Outlook.
- Open the email you wish to view the headers of.
- Click File → Properties.
- Headers will display in the "Internet headers" box.
Apple Mail
- Open Apple Mail.
- Open the email you wish to view the headers of.
- Click View → Message → All Headers.
- Headers will display in the window below your inbox.
Source: https://support.apple.com/guide/mail/show-detailed-email-headers-mlhlp1089/mac
Yahoo Mail
- Click on an email to open it.
- Click the More icon (...).
- Select View Raw Message.
Proton Mail
- Web App
- Log in to your account at mail.proton.me and open an email.
- Go to More (3-dot icon) →View headers.
- Android / iOS
- Log in to the Proton Mail app and open an email.
- Tap the 3-dot menu icon at the bottom right of the screen →View headers.
Source: https://proton.me/support/check-email-headers
Zoho Mail
- Open the email whose headers you would like to view.
- Click the More Actions drop-down on the right corner of the email.
- Choose the Show Original option.
Source: https://www.zoho.com/mail/help/mail-options.html
Don't see your email client listed? Odds are that a quick search of your mail client's documentation will show you how to view email headers. If you're still having issues, give us a shout and we'll help you find them!

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