The dark web is the part of the internet made up of websites and services that can be reached only through special anonymity software, most commonly the Tor network, which hides both the users' and the sites' locations. Dark web sites, often called hidden or onion services, have addresses ending in ".onion" and are not indexed by ordinary search engines. The dark web is used by journalists, whistleblowers and people in repressive countries to communicate safely, and it is also home to illegal marketplaces selling drugs, stolen data and hacking tools, usually in exchange for cryptocurrency.
The dark web is often confused with the deep web, which simply means any web content not indexed by search engines, such as online banking pages, email and subscription databases. The dark web is a small, deliberately hidden part of the deep web. Because so much illicit trade on it is paid in crypto, it is a recurring concern for anti-money laundering regulators and for blockchain analytics firms.
Dark web in plain terms
Most websites are like shops on a high street: they have a public address, and anyone can find them on a map. Dark web sites are more like shops reached only through a maze of back alleys, where every guide along the way knows only the next turn. Neither the visitor nor the shop needs to reveal where they really are.
That secrecy protects a reporter talking to a source, or a person reading banned news. It also protects people selling things that are against the law. Because they cannot use banks or cards without revealing themselves, many of those sellers ask to be paid in cryptocurrency.
How it works
The Tor network routes internet traffic through a series of volunteer-run relays, wrapping it in several layers of encryption, a technique described under onion routing. Each relay knows only the previous and next hop, so no single point can link the user to the destination. Hidden services extend this so that the website's server location is also concealed. Onion routing was developed by researchers at the US Naval Research Laboratory in the 1990s, and the non-profit Tor Project has maintained the software since 2006. Other anonymity networks, such as I2P, work on similar principles. Some crypto wallets support Tor integration to hide users' IP addresses.
Dark web markets and crypto
The best-known dark web market, Silk Road, operated from 2011 until the FBI shut it down in 2013. It used bitcoin for payments and was among the first large-scale real-world uses of the currency. Its founder, Ross Ulbricht, was sentenced to life in prison in 2015 and was pardoned by President Donald Trump in January 2025. Successor markets such as AlphaBay, closed by international police action in 2017, and Hydra, a Russian-language market seized by German authorities in 2022, handled large volumes of drugs, forged documents, stolen card data and money laundering services. Over time, many markets shifted from bitcoin towards Monero and other privacy coins, because bitcoin's public ledger made users easier to trace.
Financial crime on the dark web
Beyond drugs, the dark web hosts trade in data from data breaches, stolen login credentials, card numbers, fake identity documents used for identity theft, and malware, including ransomware offered as a service. Criminals use the proceeds of such sales in schemes described under cryptocurrency money laundering, often passing funds through mixers before cashing out. Banks and payment firms monitor dark web forums for leaked customer data and to anticipate fraud campaigns.
Law enforcement and legitimate uses
Police agencies have repeatedly infiltrated and shut down dark web markets, often by exploiting operational mistakes by administrators or by tracing cryptocurrency flows to exchanges that identify their customers. Seized servers have revealed buyers and sellers, leading to arrests worldwide. At the same time, many reputable organisations run onion services, including major news outlets and social networks, so that readers in censored countries can reach them safely, and secure drop systems let whistleblowers send documents to journalists. Researchers have also shown that users can be identified through mistakes such as reusing usernames, logging in without Tor or sending coins to their own exchange accounts. Debates over the dark web mirror wider arguments about privacy and anonymity, discussed under privacy-enhancing technologies.