What Is Tor?
Tor (The Onion Router) is a decentralized network designed to enable anonymous communication over the internet. Originally based on technology developed at the U.S. Naval Research Laboratory, it is now maintained by The Tor Project, a nonprofit organization.
The name "Tor" derives from "Onion Routing." Communication data is wrapped in multiple layers of encryption — like the layers of an onion — and relayed through several servers, making it extremely difficult to link the source and destination of a communication.
How the Tor Network Works
Traffic on the Tor network passes through three relays in sequence.
1. Guard Node (Entry Node)
The first relay your device connects to. It knows your IP address but cannot determine your final destination. For security reasons, the guard node remains fixed for a certain period.
2. Middle Node
A relay that bridges the guard node and the exit node. It only knows the IP addresses of the nodes immediately before and after it — neither the origin nor the destination of the communication.
3. Exit Node
The relay that serves as the gateway from the Tor network to the regular internet. It communicates with the destination website but cannot identify the original sender. The IP address visible to the website is that of the exit node.
Communication between each relay is individually encrypted, ensuring that no single relay can see the full picture. This is the essence of "onion routing."
Features of the Tor Browser
The Tor Browser is built on Firefox and comes with built-in Tor network connectivity.
Anonymity Assurance
- All traffic is routed through the Tor network
- Cookies, history, and cache are automatically deleted when the browser is closed
- NoScript is built in to restrict JavaScript execution
Fingerprint Countermeasures
- All Tor Browser users share an identical User-Agent string
- Window size is standardized to prevent identification by screen resolution
- Canvas, WebGL, and AudioContext fingerprinting are blocked
- Font enumeration is restricted
These measures make tracking via browser fingerprinting significantly more difficult.
Advantages of the Tor Browser
Strong Anonymity
With three relay hops and multi-layer encryption, Tor provides a level of anonymity that surpasses VPNs. Simultaneously identifying both the source and destination of a communication is extremely difficult.
Censorship Circumvention
In countries and regions where internet censorship is enforced, Tor serves as a means to access blocked websites. It is an indispensable tool for journalists and human rights activists.
Free to Use
The Tor Browser is completely free and open source. There are no monthly fees like those charged by VPN services.
Fingerprint Resistance
Because all users share the same browser configuration, individual identification through fingerprinting is extremely difficult.
Disadvantages of the Tor Browser
Reduced Speed
Routing through three relays significantly slows down browsing compared to a normal connection. It is not well suited for video streaming or large file downloads.
Blocked by Some Sites
Since Tor exit node IP addresses are publicly known, some websites and services block access from Tor. CAPTCHA prompts also tend to appear more frequently.
Exit Node Risks
Traffic between the exit node and the destination is not encrypted unless the site uses HTTPS. A malicious exit node operator could potentially intercept unencrypted traffic, so it is important to only visit HTTPS-enabled sites.
Limits of Complete Anonymity
Even when using Tor, your identity is revealed on services where you are logged in. Additionally, traffic from applications other than the Tor Browser does not pass through the Tor network.
Tips for Using Tor Safely
- Do not enter personal information in the Tor Browser. Avoid logging in with your real name
- Do not resize the browser window — doing so disables fingerprint protections
- Do not install additional extensions — they may compromise your anonymity
- Always keep the Tor Browser updated to the latest version
- Only visit HTTPS-enabled sites
- Do not open files downloaded via the Tor Browser outside of Tor
VPN vs. Tor
Both VPNs and Tor are effective for privacy protection, but their characteristics differ.
- Speed: VPNs are significantly faster
- Anonymity: Tor offers stronger anonymity — VPN providers may retain logs
- Ease of use: VPNs are more convenient and protect all application traffic
- Cost: Tor is free; most VPN services require a subscription
- Use case: VPNs for everyday privacy; Tor when strong anonymity is required
For more on VPNs, see our VPN guide. You can also check your IP address and fingerprint score while using the Tor Browser on the Kakunin-san homepage.