The number of job openings exceeded the number of unemployed Americans by the largest margin on record in April, signaling difficulty for employers to find workers in a historically tight market.

There were a seasonally adjusted 7.449 million unfilled jobs at the end of the month, barely budging from March, the Labor Department said Monday. Meanwhile, the number of Americans seeking work in April dropped to 5.824 million from 6.211 million a month earlier.

The number of openings increased across education, retail and construction and outnumbered the unemployed by 1.625 million in April, the largest gap on records back to 2000.

The gap between job seekers and job openings shows that employers are still eager to fill roles. At the same time, though, growth in job openings is stalling, pointing to a slowdown in labor-market momentum, said Nick Bunker, economist at Indeed Hiring Lab.

“Labor demand is still strong, but it’s not just as strong or as fast as it was in a hot 2018,” Mr. Bunker said.