Brotli
Brotli is a general-purpose lossless compression algorithm. It compresses data using a combination of a modern variant of the LZ77 algorithm, Huffman coding, and second-order context modeling, providing a compression ratio comparable to the best currently available general-purpose compression methods. Brotli provides better compression ratios than gzip and deflate speeds are comparable, but brotli compressing is a slower process than Gzip compression, so gzip may be a better option for the compression of non-cacheable content.
Brotli is compatible with most modern browsers, but you may want to consider a fallback.