Well, that didn’t age well.

Mayor Bill de Blasio claimed to a liberal podcast host in a pre-recorded interview that he is putting in full days running New York City even as he mounts a quixotic presidential bid — a claim later undercut by a Post examination of his calendars.

“There is no question that if you’re running a campaign, you have to put energy into it and attention into it,” he told Pod Save America’s Jon Lovett during an interview taped on Friday.

“I don’t mean this to be pretentious, but it is true,” he added. “Yes, I do wake up every morning; in fact, start with a whole slew of emails with a whole bunch of updates and give instructions from the very beginning of the day to the very end of the day.”

But an examination of de Blasio’s official calendars published by The Post on Tuesday — just four days after the interview was taped and the day before its release — revealed Hizzoner’s absence from City Hall.

De Blasio spent just seven hours at City Hall participating in 11 meetings, calls or other activities for the entire month of May, during the two weeks before and after he launched his campaign.

Overall, there were just 152 entries on his calendar this May, down from 194 the year before, The Post’s analysis found.

One casualty of the schedule cuts was City Council Speaker Corey Johnson, who scored just one meeting with de Blasio this May — a key time for negotiations over the city’s $92 billion budget. That was down from three meetings the year before.

However, de Blasio made time for an hour-long sitdown at Gracie Mansion with the mayor of the tiny South Carolina town of Orangeburg, Michael Butler. Butler later became the only city executive in the country to back Hizzoner’s presidential campaign.