How to access wallet.dat files without using Bitcoin Core?

Is there a way to check out wallet.dat files (you know, the classic Bitcoin Core client) without needing to download the whole Blockchain? Are there any alternatives besides Electrum?

I'm not too sure because it's possible that different wallet softwares may have different types of encryption methods for their wallet dat files. What I'm sure of is that if say for example you have a wallet dat file that was initially generated via Electrum then you can re access it via Electrum. What the wallet dat file is, is basically just your seed phrase though encrypted with a password of your choice. So if you're able to access the wallet dat file then you should have your seed and your keys and that inturn means you have your wallet, addresses and transactions all loaded up as long as you are able to sync with the Blockchain fully.

Thank you, I am having trouble with Electrum.. Also, would the passphrase be visible from the start? (They do not seem pass-protected even though I used a password); only ever used them in the Bitcoin core client. Will try Electrum on another device maybe.

There's a good chance you can extract information such as the addresses by using a tool like pywallet. However, I have never used it before, and I'd be very cautious. If there's a chance you own a significant amount of coins inside there, just let it sync, and don't mess with third party software.

Thanks,. I doubt there is anything in there, just curious and perhaps I can see some old transactions too. Unfortunately, I cannot download the entire chain.. I shall continue the proven method: DIY (with a respected client)..

I can provide you the chainstate, if you're curious to know. That's a few gigabytes, but absolutely less than ~650 GB. I would absolutely stay away from both of them. Uploading private keys to any server is just a red flag.

Agreed, thanks. The chainstate is enough to check old-time-period balances?

Yes, it's basically the "address balance" related information you'd look on a block explorer. It contains the list of unspent transaction outputs. Bitcoin Core can scan your wallet with that list to tell if there's such an output unspent. When syncing with the network, what you actually want is to reach the most recent chain state without trusting anyone. The faster alternative is, of course, to do trust.

I think he's talking about Bitcoin core wallet data  but he seems to be having another issue with Electrum wallet data from his comment below your post .. I'm I right OP  ?? But I thought reindexing is kinda slow  unlike downloading the entire blockchain ( or I'm  I the one getting it wrong??  ) Because  I once tried it and later gave up to restart the sync process, although  I think some other factors contributed to it ..

I edited my post. Here's a simple way to view it: Scanning: Checks the blocks for transactions related to your wallet.Indexing: Starts from block 1 and reconstructs the UTXO set.Syncing: First you download the blocks, then you index the database. I forgot to mention that if you don't have the entire blocks directory (only pruned blocks, and chainstate), then this means you can't view your transaction history. If your wallet has any UTXOs, it will display those only. Edit: Relevant thread: https://bitcointalk.org/index.php?topic=5520755.msg64783212#msg64783212. I still insist on just letting it sync, normally, without interfering.

Okay.. understand it now!

You can use a pruned snapshot that is provided by LoyceV. His post, the pruned snapshot download link. If you trust LoyceV, use this but there are reasons to not use snapshot if you believe that you have bitcoin with considerable value in that wallet file. Do IBD is the best, safest.

I stopped updating and eventually deleted the snapshot years ago. I'm currently "between servers", so I can't easily recreate it. That temporary snapshot disappeared when my dedicated server disappeared....

Electrum gives me an error message on how it cannot read the file at a 'certain line' (whatever that means!) when I "open". The files are .dat / unsure if encryption is 'in-built' or if these are raw files.

Electrum can't open Bitcoin Core's wallet.dat. Easiest solution: install Bitcoin Core, load your wallet.dat, export the addresses and import them watch-only in Electrum. You don't need to download the blockchain to do so.

Oh, to feeling newbie once more. Thank you, seems obvious now. So, onto the next, I have checked some the addresses using the command "listreceivedbyaddress 0 true". Now, having seen an address (could there be a watch-only address inside this particular .dat?!) with funds: I first enter my passphrase to which I get "null" (odd) which then leads to "Private key for address <xyz> is not known (code -4)", when I command "dumpprivkey <xyz>" ... even though passphrase is seemingly correct (for an incorrect submission I get an "invalid passphrase" type response). Alas, seems there is not much in there so I may just accept it as 'untouchable' dust if I can't get around these hiccups ... a forced-hodl on some sats...

Maybe a full sync on Bitcoin Core is easier: if you have a decent computer and unlimited internet, it's really not that bad. Just keep it running until it's done.

Unfortunately no space or so it seems, something is off. Thank you for the help. I will try again.

A pruned node takes only 15 GB of disk space (and ideally about the same amount of RAM during IBD).

Then definitely a software/hardware thing. I will have a pruned node hopefully by end of week. If I have the space, I shall try full node'ing it.