How to change Mat-Datepicker date format to DD/MM/YYYY in simplest way?

use dateadapter from core

import { DateAdapter } from '@angular/material/core';

constructor(private dateAdapter: DateAdapter<Date>) {
    this.dateAdapter.setLocale('en-GB'); //dd/MM/yyyy

}

`

First, bind the format to your mat-datepicker.

export const MY_FORMATS = {
    parse: {
        dateInput: 'LL'
    },
    display: {
        dateInput: 'YYYY-MM-DD',
        monthYearLabel: 'YYYY',
        dateA11yLabel: 'LL',
        monthYearA11yLabel: 'YYYY'
    }
};

along with this you need to import and provide the modules.

import { DateAdapter, MAT_DATE_FORMATS, MAT_DATE_LOCALE } from '@angular/material';
import { MomentDateModule, MomentDateAdapter } from '@angular/material-moment-adapter';

{ provide: DateAdapter, useClass: MomentDateAdapter, deps: [MAT_DATE_LOCALE] },
{ provide: MAT_DATE_FORMATS, useValue: MY_FORMATS }

And in HTML follow this simply.

<mat-form-field>
    <input
        matInput
        [matDatepicker]="dp"
        placeholder="Verbose datepicker
        [formControl]="date"
    >
    <mat-datepicker-toggle matSuffix [for]="dp"></mat-datepicker-toggle>
    <mat-datepicker #dp></mat-datepicker>
</mat-form-field>

The easiest way is to change the locale:

Add the following to the providers section of your module:

{ provide: MAT_DATE_LOCALE, useValue: 'en-GB' }