The Most Durable Bitcoin Cold Wallet

Everything you need to store your Bitcoin seed securely stamped on thick metal plates and hexagonal rods.

Compatible with Trezor, Coldcard, Ledger, Electrum and any other wallets that use mnemonic seeds for backup.

Why Coldbit Steel?

Bitcoin is a remarkable form of decentralized, censorship resistant, sound money. But to reap its benefits people need to properly manage their keys.

Coldbit offers tools and guides that explain how to do proper key management in Bitcoin without relying on third parties (self custody).

Coldbit offers physical, easy to understand security for your Bitcoin keys.

Cold Steel - Physical Security

Stamping steel is the best way to preserve extremely valuable information like your Bitcoin seed.

It may not be as easy as printing a sheet of paper or encrypting a USB drive but it offers unparalleled durability and longevity to those who can do it.

Coldbit means thick, stainless steel plates and hex rods, letter and number stamps made from hardened steel and heavy club hammers rather than vulnerable electronic devices, pieces of paper and trusted third parties.

Latest blog posts

Introducing Coldbit Jig

To make stamping Bitcoin seeds onto steel easier we’ve designed and developed Coldbit Jig: This jig has the following features: Better grip/control of the stamping bit (always in straight upright position, no wobble) Prevents the bit from flying across the room and as a consequence protects your eyes Protects your fingers Enables multiple punches in […]

What types of mnemonic seeds are used in Bitcoin?

There are essentially four types of mnemonic seed phrases used in Bitcoin: BIP39 Electrum Shamir Shares (SLIP39) LND (AEZEED) Why do they exist? What makes them different from each other? Can we identify them easily? In this short guide we’ll try to address these questions.  What’s the purpose of mnemonic seed phrases? The main purpose […]

Can BIP-39 passphrase be cracked ?

In a recent post about BIP-39 I described how mnemonic sentences in the context of Bitcoin work and what makes them secure. 128 or 256 bit cryptography is considered secure and unbreakable now and for the foreseeable future. It’s the basis on which Bitcoin wallet security depends on. Can the same thing be said about […]

Extreme stress test of Coldbit Steel – will it survive?

Last year (2018) Jameson Lopp performed an extreme stress testing of a few Bitcoin metal wallets (BIP-39 seed backup). At that time Coldbit Steel was in the design phase and I took the first test results into consideration when designing it. This year I’m happy to announce that both Coldbit Steel and Coldbit Passphrase survived […]

BIP-39 basics. From randomness to mnemonic words.

Have you ever wondered how your Bitcoin wallet seed words (mnemonic words) guard access to your wallet funds and what makes such setup secure ? In this article we’ll dive into the basics of BIP-39 which describe what seed words are and how we can use them to backup our wallet keys in a recoverable […]

Introducing Coldbit Passphrase – your BIP39 passphrase backup on stainless steel

Since we have the seed word metal backup covered wouldn’t it be nice to be able to backup your BIP39 passphrase(s) as well on a piece of meta that lasts a very long time and is resistant to fire and flood ? The fact that we were offering a product that let you stamp your […]

No products in the cart.