The dollar was 0.47 percent higher against the Japanese currency at 109.87 yen.
The BoJ cut its inflation forecasts but maintained its stimulus program, with Governor Haruhiko Kuroda warning of growing risks to the economy from trade protectionism and faltering global demand.
"They are conceding that the risks to inflation and growth are skewed to the downside," said Minh Trang, senior currency trader at Silicon Valley Bank in Santa Clara, California.
"Of course, that is going to be bearish to the yen."
Against a basket of six major currencies the greenback was about flat on the day.
"The trade conflicts and tensions, the shutdown and certainly more chatter about global growth in 2019, those are the factors that need to be hashed out before we get a clear direction," said Trang.
Currency traders' attention now shifts to the European Central Bank, which meets on Thursday where market watchers expect it to acknowledge growing threats to the euro zone economy.
Sterling rose above $1.3 after Britain's opposition Labour Party said it was "highly likely" to back an attempt by lawmakers to prevent a disorderly no-deal Brexit.
The Canadian dollar edged higher against its US counterpart, recovering from an earlier two-week low, as gains for stocks and oil prices offset domestic data showing a bigger-than-expected drop in domestic retail sales.