Coldcard Mk4

Coldcard Mk4 is a non-custodial and open-source hardware wallet. Coldcard Mk4 has no known history of private key compromise, hacks, or manufacturing scandals. Coldcard Mk4 stores seed data and private keys within its dual secure elements (Microchip ATECC608A and ST33). Security is enhanced through BIP39 seed phrase recovery, encrypted PIN entry with anti-phishing words, passphrase support, and optional “duress”, “brick-me”, and “BIP85 child seed” modes. Firmware integrity is verified by signed releases, and all cryptographic operations occur in-device.

Coldcard Mk4 was created by Coinkite Inc., a company founded by Rodolfo Novak, and Peter D. Gray.

Coinkite Inc., the company behind Coldcard Mk4, is headquartered in Toronto, Ontario, Canada.

Coldcard Mk4 is initialized via a setup process where a PIN (prefix + suffix) is paired with anti-phishing words. Coldcard Mk4 connects via USB-C, supports NFC and uses MicroSD for PSBT import/export and all transaction signing is done internally using dual secure elements with isolated decryption.

Coldcard Mk4 was released October 05, 2022-