Code
<!DOCTYPE html>
<html>
        <head>
                <title>html tutorial - html5 - html code - html form - In 30Sec by Microsoft Award MVP - | wikitechy HTML step attribute</title>
        </head>
        <body>
                <form action="step.html" onsubmit="alert('Submitted!');return false;">
                
                        <input type="number" name="point" step="5">
                        <input type="submit">
                </form>
        </body>
</html>





Result