How Tor and onion services work, explained from scratch

Plain-language guides for people starting from nothing. Every term defined the first time it appears, every step shown, and no assumption that you already know how any of this fits together.

Start with the beginner guide Browse every topic

The path through the material

Each stage assumes you have finished the one before it. If something is unclear, the earlier stage is where the missing piece usually is.

  1. Understand the basics

    What the thing actually is, what problem it solves, and the handful of terms you need before anything else will make sense.

    Read the introduction
  2. Set it up yourself

    A walkthrough you can follow on your own machine, with the common mistakes called out at the point where people usually make them.

    Follow the setup guide
  3. Use it well

    The habits and settings that separate a working setup from a good one, and the mistakes that quietly undo the work you have already done.

    Read the practical guide

Topics covered here

Every guide sits under one of these. Start anywhere; each one is written to stand on its own.

  • Tor basics

    Start here. What Tor is, how to install it, and what it does and does not protect you from.

    4 guides

  • Onion services

    How onion services work, why their addresses look the way they do, and how to run one yourself.

    2 guides

  • Staying safe

    The mistakes that undo everything else: deanonymisation, cloned sites, weak threat models, and what Bitcoin really reveals.

    2 guides

  • How it works

    The mechanics underneath, explained without hand-waving: relays, circuits, layered encryption, and how private browsing tools compare.

    1 guide

  • Reference

    Definitions, background and things to look up rather than read straight through.

    1 guide

Recently published

Guides are revised when the material changes. The date shown is the last revision, not the first publication.

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Questions people ask first

Do I need any background knowledge to start?

No. The introduction assumes nothing and defines each term the first time it appears. If a guide uses a word without explaining it, that is a mistake on our side.

How long does it take to get through the material?

The introduction takes about fifteen minutes. The full sequence, including the setup walkthrough, takes most people two to three hours spread over a few sittings.

Is any of this out of date?

Each guide shows the date it was last revised. Anything that has not been checked within the year carries a note saying so.

Can I use these guides somewhere else?

Quote a paragraph with a link back and that is fine. For reprinting a whole guide, get in touch first.

Who writes this

Written and maintained by a small group who kept answering the same questions and decided to write the answers down properly. Corrections are welcome and get credited.