Use the size attribute to set the number of visible options for <select> element in HTML.
Example
You can try to run the following code to implement size attribute −
<!DOCTYPE html> <html> <body> <p>Select the countries you have visited till now,</p> <select size = "5"> <option value = "india">India</option> <option value = "us">US</option> <option value = "canada">Canada</option> <option value = "aus">Australia</option> <option value = "bangladesh">Bangladesh</option> </select> </body> </html>