NGRAVE Zero Review: Is the Air-Gapped Vault Worth €398?

This NGRAVE Zero review is written for someone who has already lost coins, almost lost coins, or watched a friend lose coins, and is now trying to figure out whether spending nearly €400 on a Belgian-made hardware wallet is rational or just expensive theatre. We bought the unit ourselves, we have no affiliate relationship with NGRAVE, and we will tell you where the device disappointed us as well as where it impressed.

Short version: the Zero is one of the more seriously engineered consumer hardware wallets on the market, but it is not magic, and several of its marketing claims need qualification.

What the Zero actually is

The NGRAVE Zero is a fully air-gapped hardware wallet. There is no USB-C data port for transactions, no Bluetooth, no NFC, no Wi-Fi. All communication with the outside world happens through QR codes scanned between the device and the Liquid mobile app. The USB-C port on the device is used only for charging.

It runs on a secure element certified at EAL7 by the Common Criteria framework, which NGRAVE has stated since launch and which is referenced on the official product page (ngrave.io, accessed May 2026). EAL7 is the highest assurance level in that scheme. For comparison, most competing hardware wallets ship chips certified at EAL5+ or EAL6+. Whether that difference matters in practice for a retail user is debatable — we will get to that.

The device generates its seed using three entropy sources combined: the secure element’s hardware RNG, the fingerprint sensor, and the ambient light sensor. The intent is to defend against the scenario where a chip vendor’s RNG is backdoored or simply broken, which is not paranoia — see the random number generator weaknesses we covered in our hardware wallet entropy guide.

Setup experience

Setup takes around twenty minutes. You hold the fingerprint sensor, wave the device around to gather light entropy, and the screen displays your 24-word seed. There is no option to skip seed display in favour of a sealed shipped seed (which is good — sealed seeds are a known supply-chain risk).

The screen is sharp and large enough to read the seed comfortably. The device is heavy, around 100 grams, which feels reassuring but is irrelevant to security.

Pairing with the Liquid app on iOS or Android is done by scanning a QR code. From that point onwards, every transaction signing is a back-and-forth QR scan. This is slow. If you are an active trader, you will hate it within a week. If you are a long-term holder moving funds twice a year, the friction is the point.

For more on whether air-gapped is genuinely better than USB hardware wallets, see our breakdown in air-gapped vs connected hardware wallets.

The Liquid app problem

The Liquid app is competent but limited. It supports Bitcoin, Ethereum and most major EVM chains, Solana, and a handful of others. Coverage is narrower than Ledger Live or Trezor Suite. If you hold tokens on chains like Sui, Aptos, or some smaller L1s, you will need to use a third-party watch-only wallet that supports PSBT-style QR signing, and the workflows are not always clean.

We tested a Solana SPL token transfer and it worked, but the address verification on the Zero’s screen showed the full base58 address in a font that required attention. That is a design choice, not a flaw — you should be reading the full address — but it is not friction-free.

Desktop support exists through a companion app but is less polished than the mobile experience. NGRAVE has been promising broader desktop functionality for over a year. We have not seen it ship at the pace announced.

Security claims, scrutinised

NGRAVE markets the Zero as “the coldest wallet.” The phrase is marketing, but the underlying claims hold up better than most:

• EAL7 chip: confirmed via the published Common Criteria certification report referenced on NGRAVE’s site.
• Air-gap: confirmed. There is genuinely no radio or data port.
• Open-source OS: the operating system layer is open-source on NGRAVE’s GitHub. The secure element firmware itself is not, because the chip vendor does not permit it. This is the same constraint every hardware wallet faces.

What the Zero does not do:

• It does not protect you from a compromised Liquid app on a malicious phone. The QR you scan still has to be one you trust the contents of.
• It does not eliminate the seed phrase. Lose your 24 words, lose your funds. The Graphene steel backup is a separate €149 product.
• It is not quantum-resistant. Like every Ledger, Trezor, Coldcard, and Keystone on the market, it uses elliptic curve signatures that would be broken by a sufficiently capable quantum computer. We have written about why this matters less in 2026 than headlines suggest in our quantum threat to crypto explainer, but the marketing copy on some hardware wallet sites is misleading on this point and NGRAVE is no exception.

Price and who it is for

At €398 (NGRAVE store, accessed May 2026), the Zero sits at the top of the consumer market. A Trezor Safe 5 is roughly half that. A Ledger Stax is around €399 but with very different design priorities (Bluetooth, e-ink, connected workflow).

The Zero makes sense if:

• You hold a portfolio you cannot afford to lose to a USB-borne exploit.
• You are willing to trade transaction speed for an air-gap.
• You are mostly on Bitcoin, Ethereum, and a handful of major chains.

It does not make sense if:

• You are storing under €5,000 — the price-to-protection ratio collapses.
• You actively trade or interact with DeFi multiple times per week.
• You need broad altcoin support out of the box.

For smaller balances, our shortlist of hardware wallets under €150 covers options that handle the same core threat model at a fraction of the cost.

Could not verify

We could not independently verify NGRAVE’s claim that the device has never had a critical vulnerability disclosed. The lack of public CVE entries is consistent with that claim, but absence of evidence is not evidence of absence. The Zero has not been subjected to the same volume of public third-party teardowns as Ledger and Trezor devices, simply because fewer security researchers own one.

Honest summary

The NGRAVE Zero is a genuinely well-engineered air-gapped hardware wallet that justifies its premium for users with significant balances and a long-term holding pattern, but it is not the universal answer to self-custody, it does not solve the quantum question any better than its competitors, and the Liquid app’s limited chain coverage is a real constraint that the marketing does not flag clearly enough. Buy it for what it is — a careful, slow, deliberately inconvenient cold storage device — not for what the brochure suggests.