wa.me link and api.whatsapp.com/send: how to build a WhatsApp link with a message

If you have a business, sooner or later you need someone to message you on WhatsApp without having to save your number. The solution is a link: wa.me or api.whatsapp.com/send. Both open a conversation with your number and, if you want, with a pre-written message that the customer just has to send. It sounds simple, but there are details that make the link work or make it open nothing. This guide shows you how to build them correctly, with examples ready to copy and paste, and the mistakes we see most often.

What is a WhatsApp link and what is it for?

A WhatsApp link is a URL that, when clicked, opens the app (or WhatsApp Web) in a conversation with a specific number. You can use it on your website, in an Instagram button, in an email signature, in a QR code or in an advertising campaign. It helps remove friction: the customer doesn't have to copy your number, save it and then message you. One click and they're already talking to you.

There are two main formats: wa.me and api.whatsapp.com/send. The first is shorter and easier to remember; the second is the one used by the official WhatsApp API and allows some variations. Both accept a text parameter to preload the message. The practical difference is the length and that api.whatsapp.com/send is sometimes used when you need compatibility with systems that expect a more formal URL.

Basic format: wa.me

The structure is: https://wa.me/<number>. The number must go without the + sign, without hyphens, without parentheses and without the leading 0. For Argentina, for example, the number +54 9 11 1234-5678 is written 5491112345678. The country code goes first, then the area code without the 0 and the number without the 15. If the number is wrong, the link won't open the conversation.

• Correct example: https://wa.me/5491112345678
• Incorrect example: https://wa.me/+54 9 11 1234-5678 (it has spaces, + and hyphens)
• Incorrect example: https://wa.me/01112345678 (missing the country code and has an extra 0)

Add a preloaded message

For the message to appear written in the chat, add the ?text= parameter followed by the text. The text must be URL-encoded: spaces are replaced with %20, question marks with %3F, quotation marks with %22, and line breaks with %0A. If you don't encode it, the link may break or show strange characters.

Example: https://wa.me/5491112345678?text=Hola%2C%20quiero%20consultar%20por%20el%20producto%20X. When it opens, the customer will see 'Hola, quiero consultar por el producto X' in the typing field. They just have to tap send. This is useful for campaigns: you can have a different link for each product or service and know in advance what the customer wants.

Format with api.whatsapp.com/send

The structure is: https://api.whatsapp.com/send?phone=<number>&text=<message>. Here the number also goes without +, without 0 and without hyphens. The phone parameter is required; the text is optional. This format is the one used in the official WhatsApp documentation for click-to-chat links. The difference with wa.me is that api.whatsapp.com/send allows adding more parameters, although in practice the most used are phone and text.

Example: https://api.whatsapp.com/send?phone=5491112345678&text=Hola%2C%20quiero%20turno%20para%20mañana. It works the same as wa.me: it opens the conversation with the message already written. If your system already uses api.whatsapp.com/send, there is no need to change it; if you are building something new, wa.me is shorter and just as effective.

Comparison table: wa.me vs api.whatsapp.com/send

So you can choose without hassle, here is a table with the concrete differences.

• Length: wa.me is shorter (e.g. wa.me/5491112345678). api.whatsapp.com/send is longer (api.whatsapp.com/send?phone=...).
• Number parameter: in wa.me it goes directly in the path. In api.whatsapp.com/send it goes in the phone parameter.
• Text parameter: in wa.me you use ?text=. In api.whatsapp.com/send you use &text=.
• Compatibility: both work on mobile and desktop. wa.me is easier to remember and to write by hand.
• Typical use: wa.me for buttons and social media; api.whatsapp.com/send for integrations that already use it.

Common mistakes when building the link

The most frequent mistake is writing the number in human format: with +, with 0, with 15, with hyphens. WhatsApp expects only digits, with country code. Another mistake is not encoding the text: if you write 'Hola, ¿cómo estás?' without encoding, the question mark and the comma can break the link. It also happens that the number doesn't have WhatsApp or is misspelled, and the link shows an error message.

• Number with +, leading 0, 15 or hyphens: it doesn't work.
• Text without encoding: it can get cut off or show strange symbols.
• Using http instead of https: some browsers block it.
• Links in images or buttons that aren't clickable: check that the <a> has the correct href.
• Testing only on your phone: also test on desktop and on another device.

How to test the link before publishing it

1. 1Build the link with the correct number and the encoded text.
2. 2Open it in an incognito tab on your computer: it should show WhatsApp Web with the chat open.
3. 3Test it on your phone: it should open the app with the message preloaded.
4. 4Ask someone from another country or with another carrier to test it: sometimes there are differences.
5. 5Check that the number has WhatsApp active and can receive messages.
6. 6If you're going to use it in a campaign, measure how many clicks generate real conversations.

WhatsApp links in your customer service strategy

A well-built link is the entry point. After that, the conversation needs to be handled. If your business receives many messages, replying one by one becomes overwhelming. That's where tools like Wando help: the AI suggests replies based on the real replies your team has already given, and you approve them with one click. It doesn't reply on its own without supervision: it learns from the way you speak and speeds up customer service. Wando uses Meta's official WhatsApp API, so links and the inbox work together without problems.

If you want to try it, Wando has a 14-day free trial, no card required. You don't have to change everything at once: you can start by using links to route inquiries and, if the volume grows, add the inbox with suggestions.

Frequently asked questions

These are the questions that come up most often when someone creates their first link.

• Can I use the same link for several numbers? No, each link points to one number. If you have several, create one link per number.
• Is the pre-filled message sent automatically? No, the user has to tap send. It's a helper, not an automatic message.
• Does it work on WhatsApp Business? Yes, the link opens the conversation with your number, whether it's Business or not.
• What happens if the number doesn't have WhatsApp? The link shows an error or doesn't open the conversation.
• Can I shorten the link? Yes, with a link shortener. But be careful: some block WhatsApp links or lose the pre-filled text.

Conclusion

Creating a WhatsApp link with a message is a matter of following the correct format: number without symbols, encoded text and testing it before publishing it. wa.me is shorter and easier; api.whatsapp.com/send is the one many integrations already use. With a well-made link, every click becomes a conversation. After that, customer service depends on your team and the tools you choose. If you want to know how Wando can help you reply faster, visit wando.online.