How to add password matching validation in vuetify?

very easiest way is using v-model (password and confirm_password), no need to use computation

Rule

:rules="[v => !!v || 'field is required']"

Or

:rules="[(password!="") || 'field is required']"

in password

<v-text-field label="Password*" v-model="password" type="password" required   :rules="[v => !!v || 'field is required']"></v-text-field>
         
       

confirm password field Rule

 :rules="[(password === confirm_password) || 'Password must match']"

code:

 <v-text-field label="Confirm Password*" v-model="confirm_password" type="password"  required   :rules="[(password === confirm_password) || 'Password must match']"></v-text-field>
         


           

You can define custom rules:

computed: {
    passwordConfirmationRule() {
      return () => (this.password === this.rePassword) || 'Password must match'
    }
}

and use it

 <v-flex xs12 sm6>
    <v-text-field            
      v-model="rePassword"
      :append-icon="show1 ? 'visibility' : 'visibility_off'"
      :rules="[rules.required, rules.min, passwordConfirmationRule]"
      :type="show1 ? 'text' : 'password'"
      name="input-10-1"
      label="Re-enter Password"
      hint="At least 8 characters"
      counter
      @click:append="show1 = !show1"
    />
  </v-flex>