i18nPlural pipe

Maps a value to a string that pluralizes the value according to locale rules.

See CLDR — Plural Rules.

Source
<input [(ngModel)]="value">
{{ value | i18nPlural: mapping }}
export class AppComponent {
  value = 1;

  mapping: {[k: string]: string} = {
    '=0': 'No messages.',
    '=1': 'One message.',
    'other': '# messages.',
  };
}
Result
One message.