I'm not a math expert but I think it should take 20,825 times longer (583=195,112)*. There is also the fact that the underlying algorithm will also be different that lacks most of the pre-computation that the current algorithm for known missing places has so it will be slightly slower. However, as I said before I have no idea how to generalize this so I hardcoded the heck out of it (only for this special case: missing 3 chars, probably will add a couple more smaller cases later), the benefit of it is that I know how to run it in parallel so the more threads your CPU has the faster it would run and I don't think 4 billion is going to take that long to finish. * The problem with not knowing the missing places is that you'll have to first select different locations then loop through the 58 possible characters and keys are long (52/51 characters) so things get out of hand quickly. Example: 20,825 in last example (like others) is calculated using combination in mathematics which is n!/[k!(n-k)!] where n is 51 for compressed keys (52 char long with first one fixed to K or L) and k is 3 (the 3 missing places). Here is a preview, will publish a released version soon (the checkbox needs to be selected to enable this "special" case):
I'm not a math expert but I think it should take 20,825 times longer (583=195,112)*. There is also the fact that the underlying algorithm will also be different that lacks most of the pre-computation that the current algorithm for known missing places has so it will be slightly slower. However, as I said before I have no idea how to generalize this so I hardcoded the heck out of it (only for this special case: missing 3 chars, probably will add a couple more smaller cases later), the benefit of it is that I know how to run it in parallel so the more threads your CPU has the faster it would run and I don't think 4 billion is going to take that long to finish. * The problem with not knowing the missing places is that you'll have to first select different locations then loop through the 58 possible characters and keys are long (52/51 characters) so things get out of hand quickly. Example: 20,825 in last example (like others) is calculated using combination in mathematics which is n!/[k!(n-k)!] where n is 51 for compressed keys (52 char long with first one fixed to K or L) and k is 3 (the 3 missing places). Here is a preview, will publish a released version soon (the checkbox needs to be selected to enable this "special" case):

I'm not a math expert but I think it should take 20,825 times longer (583=195,112)*. There is also the fact that the underlying algorithm will also be different that lacks most of the pre-computation that the current algorithm for known missing places has so it will be slightly slower. However, as I said before I have no idea how to generalize this so I hardcoded the heck out of it (only for this special case: missing 3 chars, probably will add a couple more smaller cases later), the benefit of it is that I know how to run it in parallel so the more threads your CPU has the faster it would run and I don't think 4 billion is going to take that long to finish. * The problem with not knowing the missing places is that you'll have to first select different locations then loop through the 58 possible characters and keys are long (52/51 characters) so things get out of hand quickly. Example: 20,825 in last example (like others) is calculated using combination in mathematics which is n!/[k!(n-k)!] where n is 51 for compressed keys (52 char long with first one fixed to K or L) and k is 3 (the 3 missing places). Here is a preview, will publish a released version soon (the checkbox needs to be selected to enable this "special" case):

I'm not a math expert but I think it should take 20,825 times longer (583=195,112)*. There is also the fact that the underlying algorithm will also be different that lacks most of the pre-computation that the current algorithm for known missing places has so it will be slightly slower. However, as I said before I have no idea how to generalize this so I hardcoded the heck out of it (only for this special case: missing 3 chars, probably will add a couple more smaller cases later), the benefit of it is that I know how to run it in parallel so the more threads your CPU has the faster it would run and I don't think 4 billion is going to take that long to finish. * The problem with not knowing the missing places is that you'll have to first select different locations then loop through the 58 possible characters and keys are long (52/51 characters) so things get out of hand quickly. Example: 20,825 in last example (like others) is calculated using combination in mathematics which is n!/[k!(n-k)!] where n is 51 for compressed keys (52 char long with first one fixed to K or L) and k is 3 (the 3 missing places). Here is a preview, will publish a released version soon (the checkbox needs to be selected to enable this "special" case):