HTML Link & Heading Extractor
About HTML Attribute Reference
The HTML5 Attribute Reference & Specification Guide provides instant lookup for all global attributes (`class`, `id`, `hidden`, `tabindex`, `data-*`), element-specific attributes (`src`, `href`, `loading`, `srcset`), and ARIA accessibility roles.
How to Use HTML Attribute Reference
Step 1
Search for an attribute name (e.g. `srcset`, `rel`, `crossorigin`).
Step 2
Review supported HTML tags, permitted values, and code syntax.
Step 3
Copy the attribute snippet into your HTML code.
Practical Use Cases for HTML Attribute Reference
Verifying Permitted Attributes for HTML Elements
Verify whether an attribute is standard on a given element (e.g. `loading="lazy"` on `<img>` and `<iframe>`) to avoid validation warnings.
Configuring Form Input Attributes
Look up valid values and regex patterns for `pattern`, `autocomplete`, `inputmode`, `min`, `max`, and `step`.
Input & Output Examples
Looking Up `loading` Attribute
Attribute: `loading`
Supported Elements: `<img>`, `<iframe>` | Values: `"lazy"`, `"eager"` | Purpose: Defers loading until element reaches viewport threshold.
Key Features & Performance
- ✓Catalog of 200+ global and element-specific HTML attributes.
- ✓Categorized by: Global Attributes, Event Handler Attributes, Form Attributes, Media Attributes, and ARIA attributes.
- ✓Shows valid value types, default values, and code usage snippets.
- ✓100% Client-Side memory execution.
- ✓1-Click Copy attribute usage snippet.
Key Terminology & Definitions
Global Attribute
An attribute common to all HTML elements, valid on any standard element (e.g. `class`, `id`, `style`, `title`, `dir`).
Boolean Attribute
An attribute whose presence represents the true value, and absence represents the false value (e.g. `disabled`, `checked`, `required`).