It’s in the headers. Send an email to your self from Mail and open the source in the inbox. There is your IP.

xoa 2 days ago | parent | next [-]

I also just tried this as well, sending an email from a Migadu-based account to one at both Gmail and MXRoute using Mail.app under macOS 15.7.7. Neither included any private IP address info I could find in either headers or raw source. That would be a good leak to know about and as sibling comment said saagarjha definitely knows their stuff, so any tips to replicate would be appreciated.

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fckapple 2 days ago | parent [-]

Received: from smtpclient.apple (ptr. [ip]) by smtp.gmail.com with ESMTPSA id ... for <...> (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Thu, 02 Jul 2026 ..:..:.. -0700 (PDT)

Using Mail: Version 16.0 (3864.600.51.1.1).

Sent from a Google Apps mail.

	▲	jijijijij 2 days ago \| parent \| next [-]
		For me that IP belongs to apple, when using the iOS mail client. I presume Apple forces third party apps to use their API and then stuff like this happens. Guess that's also on google, not mitigating that issue, tho. Have you tried a VPN? I wonder, if Apple manages to expose IP despite a VPN. They had issues with stuff like that before.
	▲	js2 2 days ago \| parent \| prev [-]
		That Received header is inserted by smtp.gmail.com (Google), not Apple.

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ChrisMarshallNY 2 days ago | parent | prev [-]

Is this from iOS? I just tested from MacOS, and the only IPs were for the transit and auth servers.

I'm not actually doubting it. saagarjha knows his stuff. I just don't see it, so maybe I'm holding it wrong.

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frollogaston 2 days ago | parent | next [-]

Same, I remember it being in the headers long ago but don't see it now. macOS Tahoe, Mail.app client, iCloud email sending to itself or to my Gmail, both set up in default ways, IPv6 disabled

	▲	ChrisMarshallNY 2 days ago \| parent [-]
		From what I see above, it looks like the trick is to send from Mail.app to an account read by a different app (maybe just Gmail?). I would need to test with my hosting Webmail client, so maybe tomorrow.

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fckapple 2 days ago | parent | prev [-]

See my comment here: https://news.ycombinator.com/item?id=48758444.

	▲	ChrisMarshallNY 2 days ago \| parent [-]
		I saw that, in my headers, but in my case, it was not an IP in any subnet of mine. I’ll mess around, today, and see what comes up.