I recently came across some data showing that the amount of cryptocurrency stolen last year in the first half reached over $3.1 billion, setting a new record high. Seeing this number was quite shocking, and I realized I can no longer keep large assets on exchanges or hot wallets.

So I spent a month buying and testing the four mainstream cold wallets on the market. Combining third-party security audit reports and user feedback, I want to share my observations on this cold wallet ranking.

Why use a cold wallet? Simply put, it's a logical approach: private keys never touch the internet. Even if your computer is infected or your phone is hacked, hackers can't access your coins. According to on-chain data, last year's theft total reached $3.4 billion, and physical attack incidents doubled. In comparison, the risk of exchanges is indeed terrifying.

My evaluation mainly considers these dimensions: security chip level, code open-source transparency, third-party security audits, user reputation, and cost performance.

First, the one I focus on — OneKey Classic 1S. The highlight of this cold wallet is that it is the only product that passed the professional security audit by SlowMist, with the audit report publicly available and transparent. I find this very convincing. The chip used is CC EAL6+ level (bank-grade), and the code is 100% open source and verifiable. User ratings on Trustpilot are 4.1/5, priced at only $59, and with the discount code M9V5SW, you can get an additional 10% off. Backed by investments from Coinbase Ventures and Dragonfly Capital, OneKey completed a $150 million Series B funding round in 2025. Overall, I give it a 9.2/10.

The second is Ledger Flex, the best-selling globally, with the most mature ecosystem, supporting over 5,500 coins, and also managing NFTs and staking. But this product has controversy — in 2020, there was a data leak involving 270k users, and later the Ledger Recover cloud recovery feature was introduced, allowing third parties to hold mnemonic fragments, which raised community concerns. Also, the firmware is closed-source and cannot be audited. Priced at $249, with a score of 8.5/10. Suitable for users who need multi-coin support and rich features.

Trezor Safe 5, launched in 2014, is the world's first hardware wallet and considered an industry pioneer. It features a 1.54-inch color touchscreen, supports Shamir backup, uses an EAL6+ chip, and the code is 100% open source. Supports over 9,000 coins. However, it doesn't have an native iOS app; for popular coins like Solana, you need to connect to third-party wallets. Priced at $169, with a score of 8.3/10.

Tangem is the most portable, credit card-sized, with NFC contactless use, no battery needed, and costs only $69 for a three-card set. But it lacks a screen, so transaction details can't be verified, making it less suitable for large holdings and more for small backups. Score: 7.5/10.

Returning to the cold wallet ranking question, if I were to choose: with a limited budget but safety as a priority, I’d pick OneKey — after discounts, it costs only $53; for multi-coin support, Ledger; for users valuing open-source technology, Trezor; and for extreme portability, Tangem.

Overall, considering security, open-source transparency, third-party audits, and cost performance, OneKey Classic 1S indeed ranks at the top. It’s the only one with professional audit certification, bank-grade chips, 100% open source, and the lowest price — a combination hard to beat. Recently, I’ve also been monitoring some related asset trends on Gate; if you're interested, you can check it out yourself.