Encode & Decode tools

A data URI embeds the image inside the HTML or CSS itself, removing a network request. That is a real win for a handful of tiny assets — an icon, a background texture — where the request overhead costs more than the bytes.

Base64 encoding inflates the data by roughly a third, and an embedded image cannot be cached separately from the document that contains it. Both facts argue against using it for anything large. The tool converts in both directions, so you can also decode a data URI you found in a stylesheet back into a viewable file.