• default

ssh-keygen -lf ~/.ssh/id_ecdsa.pub

• Specify SHA256

ssh-keygen -lf ~/.ssh/id_ecdsa.pub -E sha256

• Specify MD5

ssh-keygen -lf ~/.ssh/id_ecdsa.pub -E md5

• example output

wnoguchi@lasthope:~/repos/dotfiles-secret$ ssh-keygen -lf ~/.ssh/id_ecdsa.pub 
521 SHA256:PlJiIER70ABEtUUf+NisAwtbMmwoRvVLPONSCvFmLvg wnoguchi@lasthope.pg1x.net (ECDSA)
wnoguchi@lasthope:~/repos/dotfiles-secret$ ssh-keygen -lf ~/.ssh/id_ecdsa.pub -E md5
521 MD5:73:f8:f4:24:b1:86:54:86:9f:af:0c:fd:04:78:3f:21 wnoguchi@lasthope.pg1x.net (ECDSA)