I don't currently have a fully synced node and I have done the following to check the balance, let me know if this is correct.
I load the wallet.dat file in the Bitcoin Core app (on Mac). The app tells me that it needs to sync the entire blockchain and I say go for it. While the app is syncing the blockchain, I click on the menu Window and select Receiving Addresses.
I then check the balance of all these addresses on Blockchain.com.
Does this give me the full picture of the balance of those wallets?
It didn't.
You see, each of your wallet normally has a reserve of 1000 receiving and 1000 change addresses, using the receive tab will only display the reserved receiving addresses in the correct index order.
So if you've checked only about 20 addresses but you actually funded the 21st, then you've missed the possible transaction linked to that wallet.
Also, if it's the change address that has any balance, you wont be seeing that by using the receive tab. (
only through sync or dump)
Also, take note that the suggested dumpwallet command above defaults to your
addresstype=<address_type> config.
So you may have to repeat that 3 times (
repeat after changing the config) to dump all of the possible address types of a legacy wallet.
Lastly, if some of your wallets are the quite new "
descriptor wallet"; you wont be able to use that dumpwallet command.
However, you can export your watch-only descriptor via
listdescriptors command and import the "
extended public key" to Electrum to check for balance.
Here's how to import those to Electrum:
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