To localize the Calendar component, import the available locales from react-date-range/dist/locale and pass the desired locale object to the locale prop.
Available locale keys include ar, bg, ca, cs, cy, da, de, el, enGB, enUS, eo, es, et, faIR, fi, fil, fr, hi, hr, hu, hy, id, is, it, ja, ka, ko, lt, lv, mk, nb, nl, pl, pt, ro, ru, sk, sl, sr, sv, th, tr, uk, vi, zhCN, and zhTW.
import * as locales from 'react-date-range/dist/locale';
import {useState} from 'react'
// ... (locale mapping logic)
const [locale, setLocale] = React.useState('ja');
const [date, setDate] = useState(null);
<div style={{ display: 'flex', flexFlow: 'column nowrap' }}>
<select
style={{ margin: '20px auto' }}
onChange={e => setLocale(e.target.value)}
value={locale}
>
{localeOptions.map((option, i) => (
<option value={option.value} key={i}>
{option.label}
</option>
))}
</select>
<Calendar onChange={item => setDate(item)} locale={locales[locale]} date={date} />
</div>