In one of the few newsletters that I don’t immediately unsubscribe from, Proton periodically will share updates about new products they’re launching, new features that have been added to existing products, etc. In a recent mailing, they highlighted a product that I didn’t even know existed: ip.me
Look up IP addresses, and find your own, at ip.me
Proton VPN has long provided a free way for you to hide your IP address to protect your privacy. But the Proton VPN team has also built ip.me, a free tool that tells you your current IP address and allows you to find information about other IP addresses as well (such as https://ip.me/62.169.136.4). It also supports DNS lookups and MX record lookups, which can be helpful if you are configuring your domain name email with Proton Mail.
This type of service is frequently useful for those instances when, for whatever reason, you need to know what your public IP is. I see this sometimes with services where, as part of setting up API keys, you can limit the availability of your instance’s API connectivity to certain public IPs for additional security. There are some things that make ip.me more useful, though, in that you can also easily get information on another IP address. If you see an IP in your server logs and want to know a rough geographical area where that IP exists or what ISP is providing it, that’s a simple lookup:
The other aspect of the site is support for doing a WHOIS lookup to see what information is available about a given domain name. In 2025, though, the details for most sites should be protected behind WhoisGuard.
I’m personally pretty unlikely to ever use the WHOIS functionality since I’m more likely to just pop a terminal and use the whois command from the CLI. This is a nice segue into my favorite feature of ip.me, though, which is the CLI support. If you simply curl against it from a terminal (curl ip.me) it’ll return your public IP. This is actually super helpful since I tend to SSH into systems and not have a clue what their public IP is. Being able to easily discern this from a shell is quite handy. I previously always used the humorously named icanhazip.com for this.
While certainly not the most Earth-shattering service (there are probably hundreds of alternatives out there which can do the same thing; even typing something like “What’s my IP?” into your favorite search engine will likely give you your public address), it’s still a nice offering from Proton. While it’s ostensibly aimed at letting people verify that Proton VPN is working as expected, it offers some nice uses outside of that raison d’être.