Migrating a wallet from BitcoinQT to Electrum for offline transaction generation

[Meatzine]

So far I have taken the wallet file and securely dumped it to a text file, but there are hundreds of private keys, possibly even thousands, and I'm not sure which ones have funds in them. Is there a quick way to see which addresses the wallet has used and save some time from importing thousands of private keys into electrum? I know the value of the wallet as a whole so I can be sure when I am done, but I don't see anything online about how to do this.

This problem could also be solved if anyone knows how to import a listed wallet.txt into electrum without manually copying every single private key in the wallet.

[LoyceV]

So far I have taken the wallet file and securely dumped it to a text file, but there are hundreds of private keys, possibly even thousands, and I'm not sure which ones have funds in them. Is there a quick way to see which addresses the wallet has used and save some time from importing thousands of private keys into electrum? I know the value of the wallet as a whole so I can be sure when I am done, but I don't see anything online about how to do this.

There's an easy (GUI) way to see which addresses have balance:
1. In Bitcoin Core, click Settings > Options > Wallet > Enable coin control features > Ok.
2. Click Send > Inputs. This shows you a list of all funded addresses in your wallet.

You can also do it in the console: Click Help > Debug window. Enter listunspent.
This gives you a list in Console.