Bittrex is one of the largest crypto to crypto exchanges. It offers a large number of trading pairs, but do not allow fiat to crypto trading. Bittrex has one of the largest trading volumes in the market.
It is a reputable exchange with good record on security and is also fully regulated. They provide two factor authentication as well as a number of other options to secure funds. They are United States based and are fully compliant with all laws.
They support more than 190 cryptocurrencies and have a dynamic platform. It’s a good option for both advanced and beginner traders; providing advanced tools like candlestick charts and crosshairs, but with a user-friendly interface that is very intuitive.
Trading Fees: 0.25%

Tokens is developing a cryptocurrency exchange for ERC20 tokens that will be powered by their native Dynamic Trading Rights token. Their exchange places a strong emphasis on community driven governance. They have developed a mechanism that allows DTR token holders to be consulted about the future direction of their trading platform and what additional token pairs will be listed.

BCEX is a top 20 exchange that is aimed at the Chinese crypto market.

Trading Fee: 0%-0.2%
Withdrawal Fee: 0%-0.5%
Number of Tokens/Coins: 51