Awhile back, CSS-Tricks posted “Probably Don't Base64 SVG”, which concluded that SVGs in data: URIs are smaller used as-is instead of base64-encoded. It’s got the right idea, but there are a few complications and further optimizations. Better browser support In the provided code, we have: (Assume the ... are replaced with real SVG data) .bg { background: url('data:image/svg+xml;utf8,<svg ...> ...