Files · wallet.dat
What a wallet.dat is and why its size matters so much
A wallet.dat is a small, visually boring file that can hold a fortune. It is worth understanding what it stores, because what can be done with it — and above all what must not be done — depends on that.
What is inside
- Your keys. What allows spending. If the wallet has a password, this part is locked.
- Your addresses. Public, visible even with a password.
- The history. What you received and sent, so the program can show your balance.
- Labels and settings you added: address names, notes.
That is why a protected wallet.dat can be opened to view addresses and balance without knowing the password. Only the spending part is locked. It is a huge practical advantage: you can confirm there is money before spending a cent on recovery.
What the size tells you
| Approximate size | What it usually means |
|---|---|
| Under 100 KB | Probably empty or barely used |
| A few hundred KB | A normal wallet with moderate use |
| Several MB | Lots of history: a wallet used for years |
| Tens of MB | A great many addresses or transactions |
| 0 bytes | A broken file or a failed copy: don’t overwrite it |
Size doesn’t tell you how much money there is, but it orients you: a several-megabyte file belongs to someone who used the wallet for a long time, and that usually means there are addresses an old backup doesn’t know about. That is the classic problem I explain in wallet.dat with a forgotten password.