How to set max number of items that can be selected in react-select?

I recommend you to use a combination of custom component Menu and isValidNewOption like the following code:

// For this example the limite will be 5
    const Menu = props => {
      const optionSelectedLength = props.getValue().length || 0;
      return (
        <components.Menu {...props}>
          {optionSelectedLength < 5 ? (
            props.children
          ) : (
            <div>Max limit achieved</div>
          )}
        </components.Menu>
      );
    };

    function App() {
      const isValidNewOption = (inputValue, selectValue) =>
        inputValue.length > 0 && selectValue.length < 5;
      return (
        <div className="App">
          <Creatable
            components={{ Menu }}
            isMulti
            isValidNewOption={isValidNewOption}
            options={options}
          />
        </div>
      );
    }

Here a live example.

The idea is to prevent user to access the options after the limit X (5 in the example) and also to prevent the enter keyboard event on create through isValidNewOption prop.

a very easy way to do this is:

<Select
        value={tags}
        onChange={(v) => v.length < 4 ? setTags(v): null}
        isMulti
        name='tags'
        options={options}
        className='basic-multi-select'
        classNamePrefix='select'
      />

just add a simple ternary check for how many items you wants