Applying new, tougher standards, state education officials said Wednesday that more than half of public school students in New York City failed their English exams this year, and 54 percent of them passed in math.

The results were in stark contrast to successes that Mayor Michael R. Bloomberg had heralded in recent years. When he ran for re-election in 2009, he boasted of state test scores that showed two-thirds of city students were passing English and 82 percent were passing math.

But state education officials said that performance was misleading because those scores were inflated by tests that had become easier to pass. The scores released on Wednesday were the first attempt to establish what the officials considered a more trustworthy measure of students’ abilities.

Merryl H. Tisch, the chancellor of the State Board of Regents, said she had encouraged teachers and parents to greet the news “not with disappointment and not with anger.”