WhatsApp's click to chat feature allows you to start a conversation with someone without having a phone number saved in your address book. As long as we know this person's phone number and they have an active WhatsApp account, we can create a link to start a chat with them. Clicking on the link will automatically open a chat with the person. Clicking to chat works both on the phone and on WhatsApp Web.
How to create your own link
You should use https://wa.me/ <number> where <number> is a full phone number in international format. Zeros, square brackets or dashes should be omitted when adding the phone number in international format.
Correct form : https://wa.me/1XXXXXXXXXX
Incorrect form: https://wa.me/+001-(XXX)XXXXXXX
Create your own link with a preloaded message
The preloaded message will automatically appear in a chat text field. You should use https://wa.me/whatsappphonenumber?text=urlencodedtext where whatsappphonenumber is a full phone number in international format and urlencodedtext is the preloaded message encoded in URL.
Example : https://wa.me/1XXXXXXXXXX?text=I'm%20interested%20in%20your%20car%20for%20sale
To create a link with only one preloaded message, use https://wa.me/?text=urlencodedtext
Example : https: //wa.me/? Text = I am% 20inquire% 20about% 20the% 20apartment% 20listing`
After clicking on the link, you will be shown a list of contacts to whom you can send the message.