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Defer Attribute Test for the Script Element

This page tests the defer attribute to the script element as specified in the HTML 4.01 specification. To test the support of your own browser for the defer attribute, click on the Test Defer Attribute link. Browsers that support this attribute (IE4+ Windows) will execute scripts in a different order than browser that do not (who execute scripts as they are encountered).

Example Output

Internet Explorer 6 for Windows 2000 supports the defer attribute (see Figure 1).

Internet Explorer 6 Windows 2000 defer test output screen shows deferred execution

Figure 3: Internet Explorer 6 Windows 2000 shows deferred execution with the defer attribute

Internet Explorer for the Mac does not support the defer attribute (see Figure 2).

Internet Explorer 5.1.7 Mac defer test output screen shows sequential execution

Figure 2: Internet Explorer 5.1.7 Mac shows sequential execution despite the defer attribute