useNow.js

import { useEffect, useRef, useState } from 'react'

export default function useNow(interval = 1000) {
  const [date, setDate] = useState(() => (new Date()))

  const intervalRef = useRef()

  useEffect(() => {
    intervalRef.current = setInterval(() => {
      setDate(new Date())
    }, interval)

    return () => {
      clearInterval(intervalRef.current)
    }
  }, [interval])

  return date
}