Air-Gapped Computer (AGC)
In this guide, you will:
- Understand why an air-gapped computer provides maximum security
- Choose the right hardware for your AGC
- Set up a permanently offline computer for Bitcoin operations
Time required: 2-4 hours
Difficulty: Intermediate to Advanced
Estimated cost: $50-200 (used ThinkPad) or $0 (repurpose old laptop)
Prerequisites: Old laptop (ThinkPad recommended), USB drive with Linux
Before starting, make sure you understand:
- What air-gapped wallets are and why they provide superior security
- Private keys and why they must be protected
- Seed phrases and how they work
Why You Need an Air-Gapped Computer
An air-gapped setup takes security to the highest level. The device holding your private keys is physically isolated from the internet—it cannot be accessed or attacked remotely.
Key security measures:
- Wi-Fi and Bluetooth physically removed
- Ethernet port disabled or permanently damaged
- Never connects to any network, ever
This is the highest level of self-custody security, though it requires more technical effort than standard hardware wallets.
Use Cases for an AGC
| Use Case | Description |
|---|---|
| Seed generation | Create seeds from dice rolls with DIY Seed Guide |
| Hardware wallet verification | Verify your HWW generates correct addresses |
| Transaction signing | Sign transactions completely offline |
| Inheritance planning | Create encrypted messages for heirs |
Why AGC Over SeedSigner
| Feature | AGC | SeedSigner |
|---|---|---|
| Encryption | Store encrypted wallet backups | Stateless, unencrypted only |
| Verification | Use multiple wallets to cross-check | Single software |
| User experience | Full keyboard, large display | Small screen, camera input |
| Discretion | Looks like normal laptop | Known Bitcoin device |
| Functionality | GPG, scripts, advanced tasks | Signing only |
While SeedSigner is great for certain use cases, an AGC offers more versatility and security options.
Guide Overview
| Step | What You'll Do |
|---|---|
| 1. Types of AGC | Choose your hardware approach |
| 2. Setup | Configure your air-gapped system |
Related Guides
Use your AGC to create a truly random seed phrase with our DIY Seed Generation Guide. Dice rolls + air-gapped computer = maximum security.
For the best AGC security, replace the stock BIOS with open-source firmware:
- Libreboot Guide - Removes Intel ME completely
- Coreboot Guide - Supports more laptop models