Seed12
The Next Generation Metal Backup
Cryptosteel: Now Safe, Forever Secure
Seed12 is the newest metal backup solution from Cryptosteel. Be in control—it’s time for you to self-custody with Seed12, built to last generations, designed for security. Safely store your 12-word seed phrases offline, ideal for software, hardware and Lightning wallets, passphrases, and master passwords. The Only Purchase You Need for Lifetime Security.

Built to last
Made from space-grade steel with precision manufacturing and top-quality craftsmanship,
the Seed12 backup system is highly resistant to fire, water, and corrosion and can withstand
the harshest conditions, ensuring your critical data stays secure no matter what.
Ultimate Toughness.
Defying Destruction.
Seed12 outlasts the toughest challenges, from heavy impacts to catastrophic drops.
Defying Destruction.
Seed12 outlasts the toughest challenges, from heavy impacts to catastrophic drops.
All-in-One Security Kit.
Protecting your sensitive data depends on a robust and durable backup that must last for many years. Transform your recovery seed phrases, passphrases, private keys, and passwords into a permanent metal medium. Seed12 offers worry-free protection from cyber threats, defense to natural hazards, and resistance against time degradation. It is also modular, adapting to your personal backup needs with multiple components adjustable within one single security kit.


Protect All Your Keys and Passwords.
Seed phrases and passwords are the bread and butter of today’s digital world, from SingleSig, to Multisig and Passphrases to Shamir Secret – Cryptosteel is the common link. Regardless of which platform you’re on – Coinbase, Trezor, Ledger, or Blockstream we help protect your seed with the same unwavering level of security. Cryptosteel is more than the standard for offline seed phrase storage – it’s a symbol of equality in the world of crypto. Your data, your passwords, and any information that’s important to you will find a safe home in Cryptosteel.

Center Piece of Security
System Backup Core is the simplest unit for backing up your seed phrase, password, or private key. In matchbox-sized packaging, you’ll receive top-quality steel plates with deeply impressed letters, along with components that allow you to securely inscribe your password. The entire process is as easy as stringing beads on a thread—no tools required. The backup you create is durable and protects your secrets from natural hazards, the passage of time, and cyberattacks.



Ultimate Protection
The Seed12 Security Kit is a comprehensive set that includes everything you need to create a fully secured offline metal backup. The kit features three modules from the Seed 12 family: Backup Core, Shell Capsule, and Security Seals.
It allows you to permanently store your backup on top-quality character tiles, threaded onto the core, encase them in a protective capsule—all made from aerospace-grade steel—and secure it with a tamper-evident seal marked with a unique serial number for the highest level of protection.

Choose your product

Seed12 Backup Core
The basic unit for durable backup
$30The set includes one Seed12 core, four cotter-pins, over 12 separators and 310+ double-sided letter tiles (Aa-Zz latin alphabet)

Seed12 Security Kit
Full tamper-proof backup set
$59The set includes System Backup Core unit, the Capsule Container and the Security Seal module (three seals with the wire)
Great things come in small packages
The Seed12 system is modular by design. We’ve embraced minimalism in both form and pricing, allowing you to buy only the parts you actually need. You can now tailor your backup to precisely match your needs, ensuring you get the best solution.
FAQ
The Seed12 is designed for storing 12-word seed phrases or passwords up to 64 characters (e.g., master passwords, private keys, passphrases). Seed12 can be used without a protective capsule aka “bare seed”. It is modular, allowing for upgrades by adding a capsule and tamper-proof seals with unique serial numbers for extra security. It is compact, making it easy to hide from prying eyes.
The Cryptosteel Capsule is for storing 24-word seed phrases or passwords up to 123 characters. Unlike Seed12, the Capsule integrates the core with the capsule itself, offering enhanced protection, though it requires DIY tamper-evident solutions.
Both devices are toolless, meaning no special tools are needed for assembly, such as hammers or sharp punches. They are also erasable, allowing for error correction, quick erasing or reset, and reuse.
Seed12 is ideal for securely storing a wide range of sensitive data. In addition to 12-word seed phrases, it can be used for passphrases, private keys, and numerical PINs. It’s perfect for storing login credentials, master passphrases for password managers, NOSTR keys, and other alphanumeric passwords up to 64 characters. This makes Seed12 a versatile solution for protecting critical data, providing robust durability and security against environmental damage and tampering.
Yes, you can use a 12-word seed phrase with hardware wallets that are compliant with the BIP39 standard. These wallets support 12, 18, or 24-word seed phrases, allowing you to switch between them if needed. You can restore a 12-word seed phrase on any BIP39-compatible hardware wallet, such as Trezor, BitBox, Ledger, Blockstream, even if it was originally set up with a 24-word phrase.
To securely back up your seed phrase, consider using a durable, offline solution such as Cryptosteel devices.
The PSW-97® tamper-proof seal prevents unauthorized access to your capsule. It’s designed to be impossible to open without breaking, ensuring any tampering is immediately visible. The PSW-97® Security Seal by American Casting & Manufacturing Corp. locks easily without tools and has a breaking strength of nearly 45 kg (100 lbs). Its clear tamper evidence and durability are trusted by private, military, and government entities. Each seal includes a unique serial number for easier management of multiple metal backups.
If you have a seed phrase stored, you’ll quickly realize if you’re reading it from the wrong end. For alphanumeric passwords, we suggest implementing a system to help with orientation—such as placing three separators at the end of the secret string.
Still have questions? Get help from a Cryptosteel expert.