Self-Custody Explained
What Is a Private Key Compromise? How Keys Leak and What to Do
Main Takeaway: A private key compromise is when someone other than you gets a copy of the key, or the seed phrase behind it, that controls a crypto wallet. With that copy they can sign transactions as you. Most compromises start where the key or seed phrase touched a connected device, a photo or another person's hands. Quick Reference Term What it means here Private key The secret number that signs transactions for one address. Whoever holds it can move what that address holds. Seed phrase The 12 or 24 words (BIP39 standard) that recreate every private key in a wallet. A leaked seed phrase is a compromise of the whole wallet. Sweeper bot An automated script that watches a compromised address and moves new funds out within seconds of arrival. What Is a Private Key Compromise? A private key compromise means a second party can produce valid signatures for your wallet. The blockchain cannot tell their signature from yours,...
How to Rehearse a Seed Phrase Restore Without Typing It Into a Computer
Testing a seed phrase backup is usually described as wiping the device and restoring it. This guide breaks the check into five levels, each with what it proves and what...
Where Is Your Crypto Actually Stored? What a Hardware Wallet Really Holds
Your crypto is stored on the blockchain, not inside any wallet. What a hardware wallet holds is the private key that authorizes moving it, which is why your recovery phrase...
Can a Seed Phrase Be Guessed or Brute Forced?
A correctly generated BIP39 seed phrase carries 128 to 256 bits of entropy, far outside brute force range. Three documented failures since 2023 all...
How Crypto Cards Hold Your Money (and What Happens When an Issuer Shuts Down)
Crypto cards differ where it counts, which is who holds your balance when the card is idle. Prepaid, exchange-linked and real-time debit models compared,...
Should You Store Your Seed Phrase in a Bank Vault?
A bank vault can hold one copy of your seed phrase. Here is how to use a safety deposit box without making it your...
What Is a Secure Element Wallet? How the Chip Guards Your Keys
A secure element wallet keeps your private keys inside a certified tamper-resistant chip, so your phone stays out of the key.
Is a Hardware Wallet Safe? What It Protects, and What It Does Not (2026)
A hardware wallet is safe from remote theft, the attack behind most crypto loss, because the keys stay offline. But safe is not invulnerable....
Cold Storage for Long-Term Crypto Holding: A Plain Guide (2026)
Cold storage is the right home for long-term crypto. What holding for years actually requires: a device that lasts, a backup that outlasts it.
Is NFC Safe for Crypto? Inside Tap-to-Sign Architecture in 2026
How to store crypto offline: a plain guide to cold storage
Storing crypto offline, known as cold storage, keeps your private keys off the internet where remote attacks cannot reach them. Here is what it...
What is an NFC cold wallet? How tap-to-sign works
An NFC cold wallet signs crypto when you tap a card to your phone — the private key stays sealed in a certified secure-element...