If you have a wallet address, you can search the blockchain for transactions that are written to that wallet address . If you find any, you must then check they aren’t already “spent” but that isn’t hard either. If you have unspent transactions, then you have bitcoin “in that wallet”. if you don’t, you don’t.
Read moreCan I access my bitcoin wallet from anywhere?
A web wallet is an online service that can send and store cryptocurrency on your behalf. The main advantage of web wallets is that they can be accessed anywhere, from any device , as easily as checking your email.
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