Every form starts with the
HTML5 introduced many input types: text, email, password, number, tel, url, date, time, color, range, file, checkbox, radio, and submit. Each type provides specialized keyboard and built-in browser validation. Use the correct type for better UX.
HTML5 validation requires no JavaScript. Use required for mandatory fields, minlength/maxlength for text length, min/max for number ranges, pattern for regex validation (e.g., pattern="[A-Za-z]{3}" for 3 letters). The :valid and :invalid CSS pseudo-classes style validation states.
Every input must have a label. Associate labels using
Style form elements carefully. Set consistent widths, padding, borders, and font sizes. Use :focus styles for keyboard users. Style placeholder text with ::placeholder. Consider custom styling for checkboxes and radio buttons using pseudo-elements.
Always validate data on the server — client-side validation is for UX only. Use POST for sensitive data. Set proper encoding (enctype="multipart/form-data" for file uploads). Add CSRF tokens for protection. Sanitize all user input server-side.