Don't listen to other people. Ask 'when would I use jQuery in React?' - if you can't find a good use for it when setting up your app then don't add it. If you come across a point when you would usually use jQuery try to figure out how'd you'd solve it with a React-orientated approach.

PS - no website needs jQuery in 2017.

Some good answers at this previous q (including my own answer :))

Using React and JQuery seems like trying to dual wield hammers on the same nail without alternating swings; i.e. they both do the same things in different ways, so using them both is just going to eat bandwidth (on initial load) without any benefit and introduce unnecessary complexity.

The whole point of using any of these frameworks is to make it simpler to develop a complex front end.

You can go for the speed issue like Aakash Mallikdid. And I am not sure if I would even consider it because react is itself is not really fast unless you know what you're doing.

So I will argue about the problem of state and separate points of truth.

if you change the DOM outside of react and react does not know about it, react won't be able to get the same result on the next rendering iteration.

what you could do in theory is move the state outside of react in something like redux.

so JQuery does something -> statecontainer gets the update -> react will do something accordingly.

in theory react is just a view library, so you could use jquery to build your framework and render everything with react still react can only "see and hear" what's happening in react. it's functional so it does not care about the global state unless you patch it in.

Taste in the end. I would not use jQuery in react unless it's really necessary, which it's probably not.

Honestly I don't know why anyone qualified to work with HTML, CSS, or JavaScript would choose EITHER of them in the first place. React is dicking around with crap JS has no business doing, and jQuery is a bloated train wreck of developer ineptitude of which 90%+ has no business being used on a website.

Because my friend, React generates the virtual DOM during initialisation state (when your app starts) and after that, it directly refers to this virtually saved DOM tree to make changes to the actual DOM. Hence there is no interaction between the two. Hence any change to the DOM by external factors ( J funking Query ) will not be registered by react. React achieves it's speed by reducing reads from DOM as much as possible hence direct DOM manipulation is a big NO NO in react workflow....

If you want me to explain why react avoids reading from DOM, ask me...