Why these links fail silently
A click-to-chat link that does not work gives you nothing to debug. WhatsApp opens, says the number is not registered, and the visitor closes it. No error reaches you, and the link looks completely reasonable.
Two causes account for almost all of it. The first is a national trunk zero. In most countries a mobile number is written starting with a zero, and that zero exists only for dialling inside the country. Internationally it is dropped. Paste 0412 345 678 straight into a link and you get a number with a stray zero in the middle that belongs to nobody.
The second is a plus sign. tel: and sms: want the plus. The wa.me path does not allow it. The same number needs two different spellings depending on which link it is going into, and a builder that uses one everywhere breaks half of them.
So this shows its working: you see what you typed, what the link will actually dial, and every change made in between. No other builder surfaces that, which is why the mistake keeps shipping.
Four links, one page
Most tools in this category build a WhatsApp link and nothing else, then ask you to sign up to shorten it. These are all the same job, so they are on one page.
The WhatsApp link opens a chat with your message already typed, which measurably beats an empty chat window because the visitor no longer has to work out what to say. The call link starts a phone call on tap. The text link opens the messaging app with a draft ready. The email link fills in the subject and body, with newlines encoded so mail clients keep your line breaks instead of collapsing everything into one paragraph.
SMS gets two versions, deliberately. There is no single spelling that works on every operating system: one separator works on Android, the other on iOS, and anyone telling you there is one correct answer has not tested it on both.
What it does not do
It builds the link. It cannot tell you whether anyone tapped it, because a wa.me or tel: link reports nothing back to anyone by design. If that matters, the link needs to run through something that counts the click first, which is what Raydar does, and then hand off to WhatsApp exactly as before.
It also does not shorten anything. If you want the finished link on your own domain rather than a bare wa.me address, that is a redirect, and a redirect needs somewhere to live. For understanding a link somebody else built, the link decoder pulls it apart, and the redirect checker follows it to wherever it really ends up.