COLDCARD vs Trezor

The two makers answer different questions. Coinkite builds only for Bitcoin and designs the COLDCARD Q to stay away from computers. Trezor builds multi-coin devices around open-source firmware and its Trezor Suite app; the Trezor Safe 5 is its mid-priced model, and Trezor also sells a Bitcoin-only edition of it. This comparison draws on each maker’s documentation, published standards and the incident sources recorded in our dataset; we have not used either device.

COLDCARD or Trezor: which one fits you?

The COLDCARD Q fits if you:

• hold only bitcoin and already use, or want to choose, your own coordinator software (Coinkite requires no account and no companion app);
• want to sign without a data cable, over QR codes, NFC or microSD, on battery power;
• want to type long passphrases on a physical keyboard;
• want multisig handled on the device; Coinkite documents multisig policies on the Q.

The Trezor Safe 5 fits if you:

• hold several coins and want to manage them in one maker’s app, Trezor Suite;
• want firmware published under an open-source licence;
• want SLIP-39 Multi-share Backup, which Trezor supports from firmware 2.7.2;
• want a small device: 65.9 x 40 x 8 mm and 23 g, against 120 x 75 x 22 mm and 93 g (without batteries) for the Q.

Can COLDCARD and Trezor sign without a USB cable?

The COLDCARD Q can. Coinkite’s product page says a COLDCARD never needs to touch a computer, and the Q offers a QR scanner, NFC and dual microSD slots besides USB-C. Three AAA cells can power it, so it can run with no cable at all. Air-gapped Bitcoin signing generally moves transactions in the PSBT format (BIP-174); our air-gapped wallets guide explains the trade-offs.

The Safe 5 is a USB device. Trezor describes its USB-C port as the interface for both power and communication. The Safe 5 also lists a microSD slot, but the Trezor pages in our records do not describe using it to move transactions.

Is COLDCARD open source like Trezor?

Trezor says its software has always been open source and that users can verify and build the firmware from its GitHub repositories. COLDCARD firmware is also public, but under MIT plus the Commons Clause, which withholds the right to sell the software. The Open Source Definition rules out that kind of restriction, so COLDCARD’s code is source-available rather than open source. Both can be read and audited; the difference is what others may legally do with the code.

On chips, the Q has two secure elements from different vendors (Microchip ATECC608 and Maxim DS28C36B). Trezor’s secure element page names one chip for the Safe 5, the OPTIGA Trust M (V3), certified to Common Criteria EAL6+, and says that chip comes without a non-disclosure agreement or restricted documentation.

How do COLDCARD and Trezor backups differ?

Both can use BIP-39 recovery phrases, and both support a BIP-39 passphrase. That shared standard is the route for moving a wallet from one maker to the other.

Beyond that they split:

• The Q creates a 24-word BIP-39 seed and supports codex32 (BIP-93) shares, a Shamir scheme designed to be checked and recombined with pen and paper.
• The Safe 5 defaults to a 20-word SLIP-39 backup, and Trezor’s backup guide says you can pick 12 or 24-word BIP-39 instead when creating the wallet in Trezor Suite. Multi-share Backup splits the backup into up to 16 shares with a threshold you set.

The share formats do not mix. SLIP-39 is not compatible with BIP-39, BIP-93 says SLIP-39 shares cannot be converted directly to codex32 shares, and we found no SLIP-39 support documented for the Q. If you might switch makers later, a BIP-39 phrase keeps that option open. More in our seed phrase guide.

What security problems have COLDCARD and Trezor had?

On 30 July 2026 Coinkite published an advisory saying a firmware bug weakened seed generation on several COLDCARD models and that attackers regenerated private keys from weak seeds and stole funds. On the Q, seeds generated before standard firmware 1.5.0Q or Edge firmware 6.6.0QX are affected, unless the advisory’s exception for seeds created with at least 50 fair, independent, private dice rolls applies. Updating firmware does not repair an existing seed; Coinkite tells owners to update, create a new seed and move funds.

For the Safe 5, our records hold brand-level phishing events (unauthorised access to Trezor’s support portal in January 2024 and abuse of its support form in June 2025) and one hardware item: Trezor states the Safe 5 was not affected by the November 2024 Safe 3 supply-chain research because it uses a newer microcontroller. None of the Safe 5 entries is a seed-generation or key-extraction flaw.

How do price and multisig compare?

On 14 October 2026 the COLDCARD Q was listed at $319, marked down from $369, on Coinkite’s store, and the Safe 5 at $129 on Trezor’s US comparison page. Trezor’s Safe 7 was listed at $249; see Trezor Safe 5 vs Safe 7.

For multisig, Trezor says Trezor Suite does not support multisig wallets directly, so the Safe 5 joins multisig setups through compatible third-party software. Coinkite documents multisig policies on the Q itself.

What we could not verify

• When the COLDCARD Q first shipped.
• Whether the Safe 5’s microSD slot can carry transactions.
• How the July 2026 COLDCARD losses split by model.