DEMO: Validation of Checkbox and Radio Buttons

Select a gender, agree to the terms, then press Submit. Reset clears the form and message.

Gender
Submit the form by clicking the button

JS Validation Checkbox validation Checkbox JavaScript

HTML

<form id="terms-form" action="" method="post">
  <fieldset>
    <legend>Gender</legend>
    <label><input type="radio" name="gender" value="male"> Male</label>
    <label><input type="radio" name="gender" value="female"> Female</label>
  </fieldset>
  <label><input type="checkbox" name="agree" value="yes"> I agree to terms and conditions</label>
  <div id="my_msg" aria-live="polite">Submit the form by clicking the button</div>
  <button type="submit">Submit</button>
  <button type="reset">Reset</button>
</form>

JavaScript

const form = document.getElementById("terms-form");
const message = document.getElementById("my_msg");

form.addEventListener("submit", (event) => {
  event.preventDefault();
  const gender = form.querySelector('input[name="gender"]:checked');
  const agree = form.elements.agree.checked;

  if (!gender) {
    message.textContent = "Select gender before submitting.";
    return;
  }
  if (!agree) {
    message.textContent = "Agree to the terms and conditions before submitting.";
    return;
  }
  message.textContent = "Validation is complete.";
});

form.addEventListener("reset", () => {
  message.textContent = "Submit the form by clicking the button";
});

Checkbox Validation Validation of dropdown Listbox