The φCoherent general-purpose codec is lossless and deterministic. Here it runs in your browser against zlib at its strongest setting (level 9), the standard everyone compares against. Pick a sample, generate some text, or drop in your own file, and watch both compress the exact same bytes.

Everything runs locally via WebAssembly. Nothing you load is uploaded.  On the standard Canterbury and Calgary benchmark corpora, φ beats zlib‑9 on every file (the one exception is incompressible random data, where no codec can win).

The φ result is computed live in phi-compress-cpp (WebAssembly), the same codec we ship. zlib‑9 is computed in your browser via pako, a faithful zlib port. Sizes include each format's full container. The φ codec trades encode speed for ratio; it is optimized for size, not throughput.