WASHINGTON — With the recession apparently over, the Federal Reserve on Wednesday held a key interest rate at a record low and again pledged to keep it there for an “extended period” to foster the fragile economic recovery.

The Fed said economic activity has “continued to pick up” and that the housing market also has grown stronger, a key ingredient to a sustained recovery.

But Fed Chairman Ben Bernanke and his colleagues warned that rising joblessness and hard-to-get-credit for many people and companies could restrain the rebound.

Against that backdrop, the Fed kept the target range for its bank lending rate at zero to 0.25 percent. And it made no major changes to a program to help drive down mortgage rates.

Commercial banks’ prime lending rate, used to peg rates on home equity loans, certain credit cards and other consumer loans, will stay at about 3.25 percent, the lowest in decades.

Still, some credit card rates have risen over the last several months. Part of that reflects rate bump-ups by lenders in response to escalating defaults on credit card loans. Lenders also pushed through increases before a new law clamping down on sudden rate hikes for credit card customers takes effect early next year.

The average rate nationwide on a variable-rate credit card is 11.5 percent. Lenders charge more and credit card customers pay rates higher than the prime because the debt they run up is more risky.

In normal times, the Fed controls only short-term rates. But after the financial crisis erupted the Fed began buying longer-term Treasuries, keeping those rates lower than they’d otherwise be.

This is good news for borrowers with auto loans, some student loans, 15- and 30-year fixed-rate mortgages and some adjustable-rate mortgages. But it hurts savers and people dependent on fixed incomes who would normally be enjoying higher yields.