Yes, you can exchange on weekends and holidays.
USD：BUY ¥157.28/SELL ¥153.00
EUR：BUY ¥182.78/SELL ¥178.25
GBP：BUY ¥212.24/SELL ¥199.74
CNY：BUY ¥23.09/SELL ¥20.56
HKD：BUY ¥21.12/SELL ¥18.72
KRW：BUY ¥0.1175/SELL ¥0.0923
PHP：BUY ¥2.93/SELL ¥2.36
SGD：BUY ¥123.00/SELL ¥115.87
THB：BUY ¥5.21/SELL ¥4.40
CAD：BUY ¥115.57/SELL ¥107.08
AUD：BUY ¥107.84/SELL ¥96.15
NZD：BUY ¥94.42/SELL ¥83.97
CHF：BUY ¥194.33/SELL ¥187.94
TWD：BUY ¥5.45/SELL ¥4.66
MYR：BUY ¥42.28/SELL ¥33.53
VND：BUY ¥0.01/SELL ¥0.005