Keystone 3 Pro: hardware wallets rating breakdown
Genuinely air-gapped — no USB data, no Bluetooth, no WiFi, no NFC; QR codes and microSD only, with the USB port reduced to power. Open firmware with published build-and-verify instructions, three secure elements, a big screen, and $149.
Genuinely air-gapped — no USB data, no Bluetooth, no WiFi, no NFC; QR codes and microSD only, with the USB port reduced to power. Open firmware with published build-and-verify instructions, three secure elements, a big screen, and $149.
How the score is built
Each criterion is scored 0–10 and weighted. The median column is the middle score across every entry in this ranking, so a row reads as a position rather than a number.
| Criterion | What we measured | Weight | Score | Category median | Rank | Weighted gap |
|---|---|---|---|---|---|---|
| Security architecture | NOT claimed by the vendor's own engineering blog EAL certification · published · 2026-07-14yes, with verify docs firmware open source · sourced · 2026-07-14 · source | 30% | 7 | 6 | 4 of 13 | +0.30 |
| Clear signing | — | 15% | 6 | 6 | 4 of 13 | 0.00 |
| Recovery and seed portability | — | 15% | 8 | 8 | 4 of 13 | 0.00 |
| Company and customer-data safety | — | 10% | 8 | 7 | 4 of 13 | +0.10 |
| Connectivity and air-gap | fully — QR + microSD only air-gapped · published · 2026-07-14 · source | 10% | 10 | 6 | 1 of 13 | +0.40 |
| Assets and networks | — | 8% | 8 | 8 | 2 of 13 | 0.00 |
| Price and true cost | — | 7% | 6 | 6 | 5 of 13 | 0.00 |
| Maintenance | — | 5% | 7 | 7 | 7 of 13 | 0.00 |
Measured 14 July 2026 · weights and method · decided by connectivity and air-gap, worth +0.40 points against the median
Security architecture: 7/10
Secure element: present or not, which chip, and the actual certification level (EAL5+, EAL6+) as published by the certifying body rather than the vendor’s marketing. Then the three questions vendors like to blur into one: is the firmware open source, is the hardware design open, and are the builds REPRODUCIBLE — can you verify that the binary on your device was built from the source you just read? Audits count only when the firm is named and the report is public.
Scored 7 of 10 against a category median of 6, which places it 4th of 13 among hardware wallets on this criterion. At a 30% weight that is 0.30 points above the median contribution of the weighted total. The best score in the category is 9, the worst 2.
Clear signing: 6/10
Its own criterion, not a footnote to UX, because this is the hole the money actually leaves through. Does the device parse and display what you are signing — the ERC-20 approval amount, the swap destination, the EIP-712 payload — or does it show you a hash and ask you to trust the computer it is plugged into? Read from vendor documentation and firmware source. NOT hands-on: we have not bought these devices, and we say so rather than implying we pressed the buttons.
Scored 6 of 10 against a category median of 6, which places it 4th of 13 among hardware wallets on this criterion. At a 15% weight that is exactly level with the median of the weighted total. The best score in the category is 10, the worst 0.
Recovery and seed portability: 8/10
BIP39, SLIP39/Shamir, passphrase support. The decisive question: can the seed be restored into a DIFFERENT vendor’s wallet? If it cannot, that is vendor lock-in, and it loses points — the entire premise of self-custody is that you can walk away from the company that sold you the device.
Scored 8 of 10 against a category median of 8, which places it 4th of 13 among hardware wallets on this criterion. At a 15% weight that is exactly level with the median of the weighted total. The best score in the category is 9, the worst 5.
Company and customer-data safety: 8/10
Jurisdiction, ownership, and the history of customer-data leaks. This carries more weight than it looks: when the buyer list of a hardware wallet leaks, it publishes the names, home addresses and phone numbers of people known to hold crypto. That is a physical-safety event, not a privacy inconvenience, and it is scored as one.
Scored 8 of 10 against a category median of 7, which places it 4th of 13 among hardware wallets on this criterion. At a 10% weight that is 0.10 points above the median contribution of the weighted total. The best score in the category is 9, the worst 2.
Connectivity and air-gap: 10/10
Is the device fully air-gapped (QR or SD only), or does it require USB or Bluetooth? Which software wallets it interoperates with, from vendor documentation.
Scored 10 of 10 against a category median of 6, which places it 1st of 13 among hardware wallets on this criterion. At a 10% weight that is 0.40 points above the median contribution of the weighted total. The best score in the category is 10, the worst 2.
Assets and networks: 8/10
What the official support list actually contains, and — importantly — whether support is native on the device or delegated to third-party software with caveats. This is the vendor’s own claim; we mark it as such, because verifying it properly means buying the device and trying ten coins, which is Level C and which we have not done.
Scored 8 of 10 against a category median of 8, which places it 2nd of 13 among hardware wallets on this criterion. At a 8% weight that is exactly level with the median of the weighted total. The best score in the category is 9, the worst 3.
Price and true cost: 6/10
Vendor store price, plus any accessory the device genuinely needs to be usable. A cheap device that requires a paid dongle is not a cheap device.
Scored 6 of 10 against a category median of 6, which places it 5th of 13 among hardware wallets on this criterion. At a 7% weight that is exactly level with the median of the weighted total. The best score in the category is 9, the worst 2.
Maintenance: 7/10
Firmware release cadence and how long old models keep receiving updates — counted from the public repository’s release history, not from a promise on the website.
Scored 7 of 10 against a category median of 7, which places it 7th of 13 among hardware wallets on this criterion. At a 5% weight that is exactly level with the median of the weighted total. The best score in the category is 9, the worst 2.
Other measurements
Its nearest neighbours in this ranking
| # | Entry | Connectivity and air-gap | How it differs |
|---|---|---|---|
| 3 | Blockstream Jade | 7 | Behind by 3 on connectivity and air-gap. |
| 4 | Trezor Safe 5 (SatoshiLabs) | 6 | Behind by 4 on connectivity and air-gap. |
| 6 | Trezor Safe 3 | 6 | Behind by 4 on connectivity and air-gap. |
| 7 | OneKey Pro | 7 | Behind by 3 on connectivity and air-gap. |
Questions about this score
What does air-gapped actually mean here?
+
No data path in or out except QR codes and microSD: the USB port supplies power only, and there is no Bluetooth, WiFi or NFC. Many devices marketed as air-gapped retain a USB data connection for convenience, which reintroduces exactly the attack surface the term implies has been removed.
Is QR signing slower than USB?
+
Yes, and that is the trade. Each transaction requires scanning between the device and your phone or computer, which adds a step every time. For deliberate transfers of meaningful size it is a small cost; for daily contract interaction it becomes tedious quickly.