How to take input of radio button with only using javascript?

Question

not a form validation, without a form tag.

can anybody help me in this?

Answer 1

var radio = document.getElementsByClassName("radio");

Return the value of radio button
radio.value

if radio is checked
radio.checked

For multiple radio buttons

for(var a = 0; a < radio.length; a++) {
if(radio[a].checked) {
console.log(radio[a].value);
return;
}
}