# How long would it take for all the Bitcoin Key pairs to be calculated? [duplicate]

Is this even something one should be worried about?

• This is more fun to calculate for yourself than to ask for the answer. Why not try it and ask if you get stuck? Nov 13, 2019 at 19:45
• I guess I should take the time it takes to calculate a single key pair and multiply it with the total number of private keys, not the total number of possible addresses (to account for expected(?) collisions). So, totalTime = singleKeyPairTime * 2^256. Right? Nov 13, 2019 at 23:06
• Sure. Of course, they could be computed in parallel, so if you want the real time required to calculate all keys, you should divide by the number of machines being used. Nov 13, 2019 at 23:15
• The closest I have come to answering how long a single ECDSA key generation takes is "some milliseconds". I ran the numbers and even if you run thousands of computers in parallel + assume one computer can calculate tens of thousands of keyGenerations/s, the infinitesimally small percentage of public keys you will find in your lifetime, is simply not worth it. Nov 14, 2019 at 2:06
• Does this answer your question? How long would it take a large computer to crack a private key? Aug 10, 2020 at 9:36

`3Blue1Brown` has made a great video explaining how large 256 bit is, check it out