Is a label-tag inside a button-tag valid and / or has any UX- / ergonomic-reasons?

1. Can a button be inside a label?
2. What is label in Button?
3. Do HTML buttons need labels?
4. What attribute is used to put label in the button?
5. How do I make labels look like buttons?

Can a button be inside a label?

Elements that can be associated with a <label> element include <button> , <input> (except for type="hidden" ), <meter> , <output> , <progress> , <select> and <textarea> .

What is label in Button?

The <label> tag in HTML is used to provide a usability improvement for mouse users i.e, if a user clicks on the text within the <label> element, it toggles the control. The <label> tag defines the label for <button>, <input>, <meter>, <output>, <progress>, <select>, or <textarea> element.

Do HTML buttons need labels?

It's unneeded for a button, since a button usually carry its own accessible name. An <input type="text"/> need a separate <label> because it has typically no accessible name otherwise. This may also be a question of understandability, which is the second WCAG principle.

What attribute is used to put label in the button?

Labeling buttons

When using the <input> element to create buttons, the label is set in the value attribute of the element.

How do I make labels look like buttons?

You can style a span inside a label to look like a button. You don't need to add the button itself. The example of a modal on the page you linked to is invalid anyway as you can't put a div inside a label element. If I understand your solution, you are making the label look like a button.