  Deep learning is increasingly attracting attention for processing big data.
Existing frameworks for deep learning must be set up to specialized computer
systems. Gaining sufficient computing resources therefore entails high costs of
deployment and maintenance. In this work, we implement a matrix library and
deep learning framework that uses JavaScript. It can run on web browsers
operating on ordinary personal computers and smartphones. Using JavaScript,
deep learning can be accomplished in widely diverse environments without the
necessity for software installation. Using GPGPU from WebCL framework, our
framework can train large scale convolutional neural networks such as VGGNet
and ResNet. In the experiments, we demonstrate their practicality by training
VGGNet in a distributed manner using web browsers as the client.
