I lost an electrum password.there is not much, only 0.5 btc, can you help me?
Is that
Electrum wallet on your mobile device... or is it the desktop version? Do you not have the backup phrase (12 words?)
If it is on the mobile, you'll probably find it a bit difficult to get the wallet file without having root access to the device... without access to the actual wallet file, then johntheripper is of no use to you.