Back in early 2018, I wrote the post DuckDuckGo is not a Dark Web Search Engine in order to shed some light on this subject. It seems that there’s still a lot of confusion over this, unfortunately.
One of the reasons that it seems people get mixed up about this is that when you download the Tor Browser, DuckDuckGo is the default search engine that it uses. Perhaps it’s time for a refresher. See the definitions below:
Dark Web – parts of the “web” built on top of darknets (anonymity networks) like Tor, I2P, and Freenet. This includes Tor’s .onion sites, but also I2P’s eepsites (.i2p) and Freenet’s “freesites.”
DuckDuckGo – a clearnet search engine that doesn’t track you based on your searches (as Google and many, but not all, other search engines do).
With that out of the way, let’s see what’s mixing people up. In addition to DuckDuckGo being a default on the Tor Browser settings, it also has a Tor hidden service (.onion site), at http://3g2upl4pq6kufc4m.onion/. Even its onion site is still a clearnet search engine, though.
In other words, if you search for “onion links” on DuckDuckGo (whether it’s the clearnet or onion version), the results will show clearnet sites related to onion links. Here’s one example of that:
I found a good explanation of this at What is DuckDuckGo and how does it work?
When you click on links from Google and Bing, even in private mode, the search terms are sent to the site you’re visiting in the HTTP referrer header. When you visit that site, your computer automatically shares information, such as your IP address. This information can be used to identify you.
DuckDuckGo calls this “search leakage” and prevents it from happening by default on its search results. Instead, when you click on a link on the site it redirects that request in such a way to prevent it from sending your search terms to other sites. The sites know that you visited them, but they don’t know what search you entered beforehand, nor can they use personal information to identify you.
Because Tor is designed for anonymity and privacy, it makes sense that it would use a search engine like DuckDuckGo. In earlier versions of the Tor Browser, it used Disconnect as its default search engine.
Even so, it is possible for onion sites to sometimes show up in search results on DuckDuckGo. The reason for this is because of proxy services like Tor2web, which allow you to access onion sites without the Tor Browser (and which is potentially dangerous, depending on the site).
An example of a Tor2Web proxy service is onion.to. As I mentioned on the previous post about this subject, there are search engines for Tor as well. One of the best known ones is not Evil: http://hss3uro2hsxfogfq.onion. Not Evil searches exclusively for onion sites.
Another good example is Ahmia, which can be accessed both via the clearnet and via Tor; are you confused yet? In other words, like DuckDuckGo, it has a clearnet version (ahmia.fi) and a Tor version: msydqstlz2kzerdg.onion.
You may notice that if you do a search on the address bar of the Tor Browser, it gives you the option of using various search engines, such as DuckDuckGo, Startpage, or Google. Just as on Firefox, you can set any of these to be your preferred search engine on the Tor Browser.
In any case, hopefully this was helpful. If you have any questions or suggestions, feel free to ask in the comments. Have fun in your dark web adventures, my friends.