Common attributes by element family

Forms

• input: type, name, value, placeholder, required, disabled, readonly, checked, min/max/step, pattern, multiple, accept (files), autocomplete.
• textarea: rows, cols, wrap, plus many shared with input.
• select/option: multiple, selected, label, value.
• form: action, method, enctype, target, novalidate, autocomplete.
• label: for (matches control id).

Links & media

• a: href, download, hreflang, ping, rel, target.
• img: src, alt, width/height, loading, decoding, sizes, srcset.
• video/audio: controls, autoplay, loop, muted, poster (video), preload.
• iframe: src, sandbox, allow, loading, referrerpolicy.

Tables

• th/td: colspan, rowspan, headers (association ids).
• th: scope (col, row, colgroup, rowgroup).

These complement global attributes (next reference page). Always validate combinations against the HTML content models—some attributes only apply to certain elements.