HTML open Attribute
Definition and Usage
The open attribute is a boolean attribute.
When present, it specifies that the details should be visible (open) by default.
Applies to
The open attribute can be used on the following element:
| Element | Attribute | 
|---|---|
| <details> | open | 
Example
An open/visible <details> element:
    <details open>
  
 <summary>Copyright 1999-2014.</summary>
  
 <p> - by Refsnes Data. All Rights Reserved.</p>
  
 <p>All content and graphics on this web site are the property of the company Refsnes Data.</p>
 </details>
Try it Yourself »
Browser Support
The numbers in the table specify the first browser version that fully supports the attribute.
| Attribute | |||||
|---|---|---|---|---|---|
| open | 12.0 | Not supported | Not supported | 6.0 | 15.0 | 

