Can your ISP see that you are using a web proxy?

Start with what does not change. Your device still makes a connection, and your network still sees that connection happen. When you use TrickyBird, your browser connects to TrickyBird over HTTPS, and that is visible: your ISP or network can see a connection to TrickyBird’s own address, roughly when it happened, and how much data moved. From that, it can tell you are using a web proxy.

This is not a leak or a flaw. It is how the web works. Anything you connect to, your network can see you connecting to, the same way it sees you reaching any other site. A web proxy is not a cloak over your connection, and any tool that says otherwise is worth doubting.

So if the question is whether your network can tell you opened TrickyBird, the answer is yes. That is the part a lot of proxy marketing quietly skips.

Now the useful half. Your network can see that you connected to TrickyBird, but not which site you opened through it. When you proxy a site, its address is encoded inside the path of a TrickyBird link, so your browser only ever connects to TrickyBird. The name of the site you actually wanted is never sent to the network around you.

That holds across the places a site’s address usually shows up. Through TrickyBird, the address of the site you open never appears in your URL bar or on the page you see, which is the zero domain leakage the scheme is built around. Your network sees the trip to the proxy; it does not see the destination on the far side.

The site you open is also kept from seeing you: it sees the proxy’s connection, so your IP address stays hidden from it. Between the 2, your network learns you used a proxy, and the site learns neither who nor where you are.

No, and that is the honest word for it. Your network can detect that you are using a web proxy, because it can see the connection to TrickyBird. Some networks go further and block known proxy domains outright, which is a separate thing from being unable to see them. A web proxy is not a way to hide that you used one.

What it does do is keep the destination private from your network and keep your IP private from the site. That is a bounded, checkable claim, not a promise of invisibility. A tool that survives you opening the developer tools and looking is worth more than one that asks for faith.

Your network is one place your traffic is visible; the proxy is another, since your traffic passes through it. So the question to ask any proxy is what it keeps. TrickyBird keeps a truncated version of your IP (the /24 for IPv4, or /48 for IPv6, not the full address), the destination hostname, and basic response details, for at most 48 hours.

A shortened IP and a hostname are not a record of your browsing, and the policy is written down so you can check it rather than take it on trust. The security page lists exactly what is kept and for how long.

The point of all of it is the same. A claim you can check on the exact device and network in front of you beats a bigger claim you cannot. See the check for yourself.

2 quieter channels are worth knowing about, because they can give away more than the main connection does. A DNS leak is a hostname lookup that escapes to the network’s own resolver; a WebRTC leak is a browser feature that can hand a page your real IP. Both are the kind of thing to test rather than assume, on the exact network you care about.

When you open a site through TrickyBird, your browser never looks up the site you opened, so the destination stays out of your DNS queries to the network. What a DNS or WebRTC leak is explains both and how to check for them yourself.