Where does the converter get its rates?

The converter takes its rates from the European Central Bank's euro foreign exchange reference rates, delivered through the open-source Frankfurter service. The ECB says these rates are usually updated at around 16:00 CET every working day, and are based on a daily concertation procedure between central banks across Europe. Yen to dollar is a cross rate worked out from the euro-to-yen and euro-to-dollar rates. It is a reference rate, not a rate anyone will trade at. The Bank of Japan does not offer a free feed that a web page can use, so the site does not use it.¹