Echo JS 0.11.0

I know of these - cannot vouch for quality

http://caza.la/synaptic/#/
https://github.com/karpathy/convnetjs
https://harthur.github.io/brain/

https://github.com/xviniette/FlappyLearning
it's not a deep learning library but it includes a neuroevolution library (just ~300 lines of code). it's like a better/extended version of http://rednuht.org/genetic_cars_2/

http://lmgtfy.com/?q=JavaScript+deep+learning

If OP is asking here, maybe it's because they need an opinionated answer, don't you think?