Newly sprung Anthony Weiner came to Manhattan federal court Wednesday for a mandatory probation check-in — but was a no-show for a nearby appointment to register as a sex offender.

The former-congressman-turned-sext-creep Carlos Danger got to the Pearl Street federal courthouse at 12:10 p.m., later than expected, and stayed for two hours before hopping into a cab without a word.

Sources told The Post that Weiner had arranged a noon appointment at the Sex Offender Monitoring Unit at Manhattan Supreme Court a block away, where officials waited through their lunch hour for him.

But the office closed at 3 p.m. with nary a Weiner in sight. Sources said he has 10 days to officially register.

“He was arrogant in [federal court]. He’s fully aware he has 10 days to appear,” said one source. “He … gave no excuses on why he skipped his appearance.”