WASHINGTON — America’s employers slowed their hiring in August in the face of rising interest rates, high inflation and sluggish consumer spending, all of which have weakened the outlook for the economy.

The government reported Friday that the economy added 315,000 jobs last month, down from 526,000 in July and below the average gain of the previous three months. The unemployment rate rose to 3.7 percent, from a half-century low of 3.5 percent in July, as more Americans came off the sidelines to look for jobs and didn’t find work immediately.

The smaller August gain will likely be welcomed by the Federal Reserve. The Fed is rapidly raising interest rates to try to cool hiring and wage growth, which have been consistently strong. Businesses typically pass the cost of higher wages on to their customers through higher prices, thereby fueling inflation.

Fed officials hope that by raising borrowing costs across the economy, they can reduce inflation from a near-40-year high. Some economists fear, though, that the Fed is tightening credit so aggressively that it will eventually tip the economy into recession.

Job openings remain high and the pace of layoffs low, indicating that most businesses still want to hire and that the economy isn’t likely in, or even close to, a recession. The broadest measure of the economy’s output — gross domestic product — has shrunk for two straight quarters, meeting one informal definition of a recession.

Most economists, though, don’t think a recession will have begun until the unemployment rate has risen steadily. Even so, worries about a forthcoming recession have grown after the Fed chairman Jerome Powell, in a high-profile speech last week, made clear that to curb inflation, the Fed was prepared to continue raising short-term interest rates for the foreseeable future and to keep them elevated. 

Mr. Powell warned that the Fed’s inflation fight would likely cause pain for Americans in the form of a weaker economy and job losses.

The Fed chairman also said the job market is “clearly out of balance,” with demand for workers “substantially exceeding” the available supply. 

Friday’s jobs figures and a report earlier this week that the number of job openings rose in July after three months of declines, suggested that the Fed’s rate hikes so far haven’t restored any such balance. There are roughly two advertised job openings for every unemployed worker.

The central bank has raised its short-term rate to a range between 2.25 percent and 2.5 percent this year, making borrowing and spending steadily more expensive for individuals and businesses. The housing market, in particular, has been weakened by higher loan rates.

The jobs figures are helping fill out the economic backdrop as this fall’s congressional elections intensify. 

Republicans have pointed to high inflation to try to pummel Democrats in midterm campaigns. The Biden administration has pushed back and claimed credit for a robust pace of job growth.