First of all, my condolences for your loss.
Regarding your question, there are a few things you might want to do to check your private key.
1. Identify the Format
Private keys usually follow one of these formats:
- WIF (Wallet Import Format): Starts with
5,K, orL(Bitcoin, Litecoin, etc.). - Hexadecimal (RAW Private Key): 64 characters long (Ethereum, Bitcoin, and others).
- BIP38 Encrypted Key: Starts with
6P. - Mnemonic Seed Phrase: A series of words (BIP39).
- Other Encodings: Base58, Base64, etc.
Since yours has an “x” at the end, it might be a specific encoding used by an altcoin.
2. Check Key Length & Encoding
Try removing the x and checking if it’s a valid hexadecimal (64 characters) or Base58 key.
- If it’s 64 characters (without
x), it’s likely a raw private key for Bitcoin, Ethereum, or another ECDSA-based chain. - If it’s 51 or 52 characters long (Base58), it might be a WIF private key.
3. Derive a Public Key and Check a Block Explorer
Assuming your private key is valid, derive a public key from it and look it up in a block explorer. It should reveal to which blockchain it belongs to.
4. Use a Crypto Key Identifier
As a last resort, try using tools that identify keys for you. I’m telling you to use these tools as a last resort because you’d need to trust a third party and that is not desirable, but there are a few tools online that might help.