At the mid-market rate I found in mid-October 2026 (about ¥158 to the US dollar, from XE and Bloomberg's JPY/USD quote), ¥100,000 comes to roughly $630. Check the XE converter for today's figure.
What you actually pay can differ from that number. Card issuers often add a foreign-transaction fee of around 3%, which would push it closer to $650. Some ryokan also add a service charge or a local accommodation tax to the quoted price, so ask whether ¥100,000 is the final total or whether more will be added at checkout. If you pay in yen by card, many card networks offer the choice of paying in yen or dollars at the terminal. Choose yen, because the merchant's conversion is usually worse.
🕒 As of October 2026