Coldcard Q Review
Maximum-paranoia Bitcoin-only signing
of 10
Coldcard lists the Q at $289 with two secure elements from different vendors, reproducible open-source firmware and QR, microSD, NFC and USB connectivity. It is Bitcoin-only by design and the most expensive device here.
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Price
$289 list
Secure elements
Microchip ATECC608 and Maxim DS28C36B
Air-gap
QR, microSD, NFC, USB
Open source
Firmware, reproducible builds
Assets
Bitcoin only
Scores
Each criterion carries equal weight. The overall score is the average of these 5 scores — (5.0 + 10.0 + 10.0 + 10.0 + 4.0) ÷ 5 = 7.8.
Pros
- Two secure elements from different vendors (ATECC608 and DS28C36B)
- Firmware is open source and reproducible
- QR, microSD, NFC and USB — full air-gap possible
- Dual microSD slots for signing workflows
Cons
- $289 list price, the highest in this comparison
- Bitcoin only — no support for any other asset
- Keyboard form factor is bulky compared with a USB signer
Two elements, two vendors
Coldcard states the Q protects the master seed with two secure elements sourced from different manufacturers, Microchip's ATECC608 and Maxim's DS28C36B. That is a deliberate defence against a flaw in any single vendor's part, and no other device in this comparison publishes the same arrangement.
Reproducible builds
The firmware is open source and, Coldcard states, reproducible — meaning a technical user can rebuild it and confirm the result matches what the device runs. Publishing source is common in this category; making builds reproducible is not.
Bitcoin only, on purpose
Coldcard states plainly that, unlike Trezor and Ledger, it supports only Bitcoin in order to reduce attack surface. That costs it points on asset coverage in a rubric applied equally across the category, and it is a design decision rather than an omission.
How it compares
Ledger Nano Gen5
Named, certified chip and the widest app ecosystem
Blockstream Jade Plus
Fully open-source air-gapped signing for Bitcoin
BitBox02
Swiss-made simplicity with fully open firmware
Coldcard Mk5
Same security model as the Q at a lower price
Trezor Safe 5
Best balance of price, certification and asset support
Keystone 3 Pro
Air-gapped signing with the widest asset support
Sources
Scored from published primary sources rather than hands-on use. Every figure above comes from one of the pages below, on the date shown. Manufacturers change prices and specifications without notice — if something here no longer matches the source, tell us and we will correct it.
Frequently asked questions
How much is the Coldcard Q?
Coldcard lists $289, shown discounted to $249.21 at the time of checking on 24 July 2026.
Does the Coldcard Q support Ethereum?
No. Coldcard states the device supports only Bitcoin, deliberately, to reduce attack surface.
Nothing here is financial advice. Editorial policy · How we score · How we're funded.