Found this thread via a Google search and thought I’d mention this: https://github.com/microsoft/onnxjs 235 Benchmarks look really promising. Haven’t tried it yet.
There’s also this blog post: https://drsleep.github.io/Tutorial-PyTorch-to-TensorFlow-JS/ 171 which explains the tensorflow.js approach (pytorch --> keras --> tensorflow.js).
I think tensorflow.js is in the process of converting their code to WebAssembly, so perhaps the benchmarks with onnx.js will be much closer once that is finished.