Binance, liqui, hitbtc and bittrex. All of them is the best exchange site in my opinion but they are all not guarantee about your safety caused by most of the hacked case started from the owner's fault.
Wow! I know all the mentioned and this list is good one. I support the above post.
But, I need to take a closer look into Binance, which is unknown exchange for me.
Interesting world.! More and more exchanges are see the day-light.
Competition is good!
p.s.
I must say that I like one more exchange called Tidex.
p.s.
Ahhh .... and in one post someone mentioned changelly.com which is also unknown for me. Must investigate further. Thanks for info.