I'm missing 22 characters out of 64 characters of my private key. I'm pretty sure I also know the first four, leaving out only 18 characters to find. Are there any ways to brute force this against my address?

3 Answers 3


18 hex characters is 72 bits, which gives 4722366482869645213696 possible combinations. A powerful bitcoin miner that you could buy is capable of calculating a hashrate of 100 TH/s or 1000000000000 hashes per second, which would take up to 150 years to find the key, and a tremendous amount of energy, not to mention having to check each key against the blockchain. Although if you had the entire bitcoin network hash rate at your disposal, it would only take about 15 seconds. So sorry but I'm afraid it's not possible at this time.


Well, each character could be one of 16 valid hex numbers (0-9/a-f), if you're missing 18 characters, you potentially have 16^18 combinations to try, that's about 5 quintillions. assuming you can test a billion a second (which is already extremely optimistic), that'd take about 150 000 years. So unfortunately, your answer is most likely no


Yes, but not in a reasonable amount of time.

You are not brute-forcing anything technically, and you don't need to check the blockchain, but you need to compute a public key from the private one and comparing the result with the public key you already know. If you don't have the public key and only have the address, the process takes much longer (you have to hash the public key to obtain the address and then compare your address).

Suppose we assume the best case (you have the public key), taking a fast lib (i.e., https://github.com/paritytech/libsecp256k1), a fast consumer general purpose processor (i.e., i7-12700k, 400k key per second), and your key in the middle of the random set of key and not the last one you check (i.e., 2722366482869645213696 keys). In that case, finding the key takes around 215 million years.

Dedicated hardware can increase substantially the computation power for specific tasks, but even with, let's say, an x1000 performance increase, you still need to wait 215.000 years — or 215 years if you use 1000 devices in parallel.

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