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Crypto without losing it
Safety basics for holding crypto: seed phrases, self-custody, fake airdrops, address poisoning and token approvals. Safety, not investment advice.
Seed phrase
The 12 or 24 words that can restore a wallet. Anyone who has them controls the funds.
Self-custody
Holding your own keys. No exchange can freeze your funds, and nobody can recover them if you lose the keys.
Custodial wallet
An account where a company, often an exchange, holds the keys for you.
Private key
The secret that signs transactions for an address. Your seed phrase generates it.
Hardware wallet
A small device that keeps keys offline and asks you to confirm each transaction on its own screen.
Address poisoning
A scammer sends a tiny transaction from a look-alike address, hoping you'll copy it from your history.
Token approval
Permission you give a smart contract to move your tokens. A malicious one can drain them later.
Fake airdrop
Free tokens appear in your wallet with a link to "claim" them, which leads to a site that drains it.
Network fee (gas)
What you pay to have a transaction processed. It rises when the network is busy.
Irreversible
A confirmed transaction can't be undone, so money sent to the wrong address is usually gone.
Wrong network
Sending a token on one blockchain to an address or exchange that expects another, which can lose it.
A "support agent" in a chat asks for your seed phrase to fix a sync problem. What do you do?
- Share it in a private message
- Share only the first half
- ✓ Never share it; real support never asks
- Send it by email instead
Where is the safest place to keep a seed phrase?
- A photo in your phone
- A cloud note
- ✓ Written down offline and stored somewhere secure
- A screenshot emailed to yourself
You copy an address from your history and the first and last characters match. Why check the whole thing?
- Fees change
- ✓ Address poisoning uses look-alike addresses
- Addresses expire
- Networks rename addresses
Free tokens you didn't ask for appear with a "claim your reward" link. What's the best response?
- Claim them before they expire
- ✓ Ignore them and don't visit the link
- Sell them on the linked site
- Approve the contract to check it
Why review the token approvals you've given?
- They charge a fee every day
- ✓ A forgotten approval can let a contract take your tokens later
- They lock your wallet
- They raise network fees