Washington has been criticized by some activists for moving too slowly to settle those fleeing the conflict, while Obama's opponents warn their number may include terrorists.
But Kerry said on Tuesday the United States is now on course to admit 10,000 vulnerable refugees, chosen from UN camps and vetted by US security and intelligence agencies.
"It's also representing six-fold increase over what we did the year before," Kerry said, referring to the US fiscal year, which runs from October 1 to September 30.
"I'm proud to say that the United States is by far the largest contributor of emergency aid, but we all recognize that still more needs to be done," he said.
Kerry made the remarks at a dinner in Washington shortly before he was due to set off on a tour of European capitals, AFP reported.
This journey was to take him Friday to Moscow, where he is set to meet with Russian President Vladimir Putin and lobby Russia to do more to help end Syria's five-year-old conflict.
Syria is in the grip of what Kerry called the worst humanitarian crisis since World War II, and more than 4.8 million people have fled the country.