Automatically generated HTML, as produced by WYSIWYG programs, typically contains much repetitive and unnecessary markup. Thispaper identifies aspects of such HTML that may be altered whileleaving a semantically equivalent document, and proposes techniques to achieve optimizing modifications. These techniques include attribute re-arrangement via dynamic programming, the use of style classes, and dead-coderemoval. These techniques produce documents as small as 33% of original size. The size decreases obtained are still significant when the techniques are used in combination with conventional text-based compression.