Lose this file, lose your bitcoin. Let someone else read it, lose your bitcoin. Corrupt it, lose your bitcoin. Understanding wallet.dat isn't just for developers—it’s for anyone serious about self-custody on the Bitcoin network.
Bitcoin Core saves the wallet.dat file inside its default data directory. The location varies depending on your operating system. C:\Users\ \AppData\Roaming\Bitcoin\ Bitcoin Core Wallet.dat
If you restore an old wallet.dat into a new node installation, the software will need to "rescan" the blockchain. It must check every block in history to see if any transactions were sent to the addresses in your wallet file. This can take hours, but it is a necessary part of syncing your history. Lose this file, lose your bitcoin
Regularly back up your wallet.dat file. This ensures that you can recover your funds if something goes wrong with your current wallet file. Understanding wallet
If you have a backup, simply stop Bitcoin Core, copy your backup wallet.dat file, and paste it into the default Bitcoin data directory, replacing the existing file.
Bitcoin Core is the original software client used to interact with the Bitcoin network. Unlike modern "light" wallets that rely on central servers, Bitcoin Core downloads and validates the entire Bitcoin blockchain.