Multi-hyphenate performer Harry Connick Jr. enters the daytime arena Sept. 12 with the premiere of “Harry” (4 p.m. on WNYW/Ch. 5).

Just don’t call it a talk show.

“I don’t really call it anything,” says Connick, 48. “I know people want to call it something, so I think an ‘entertainment show’ is probably best. It’s tough to describe.

“When we pitched it, we said, Let’s do something based around all the things I love to do, as opposed to plugging me into an existing format,” says Connick, a three-time Grammy winner who’s sold nearly 30 million albums worldwide and spent the last three seasons judging “American Idol” with Jennifer Lopez and Keith Urban. “And that’s what we did. We think it’s going to be inherently different.”

“Harry” will originate from a studio on West 57th Street with former “Late Show” head writers Justin and Eric Stangel among its executive producers.

(In a weird “perfect storm” of TV synergy, the show is produced by NBC, shot at CBS and airs on Fox.)

Here Connick tells The Post about “Harry” and about the challenges of producing a new daily TV show.

Will you have a set format?

No. I’m not going to come out and do a monologue and then have three guests. Some days there won’t be any celebrity guests. It’s not a celebrity-driven show. Some days we’ll celebrate everyday folks in extraordinary ways. Some days I might tell stories.

‘Some days there won’t be any celebrity guests. We’ll celebrate everyday folks in extraordinary ways.’ - Harry Connick Jr.

And you’re working with your regular band?

My band is the band that’s on the show every day. We’re going to have music but not a house backup band. These are musicians I play with all the time and have a close relationship with and who are really good at doing anything and everything at a moment’s notice. Any kind of whim I have, they’re able to pull things off. I’m the guy who writes all the music, those five seconds of music you hear leading into a commercial … and when we come out of a commercial, maybe I’ll want to keep playing. Maybe I’ll be up on the bandstand playing with the guys for two more minutes. I don’t really know what’s behind the curtain half the time — or all the time, really — so it’s that type of discovery process along with the audience. It’s very similar to what I do on stage. That’s a world I feel very comfortable in.

The ratings bar in daytime has been lowered significantly. Do you think this will benefit you?

To be honest with you, that’s the last thing I think about. You probably don’t believe that at all … but if I thought about how popular something was going to be when I did it, I can promise you I wouldn’t have made half the choices I made. I did a record with Branford Marsalis, just the two of us. Getting on stage with Branford is like getting into the ring with [Mike] Tyson. It’s no joke. Had that record [“Occasion”] sold 5 million copies, it would’ve been awesome, but it didn’t. A lot of people don’t even know about it, but it’s one of my crown jewels. Same thing with this show. If the show does great, everyone will be jumping up and down. If it doesn’t, I’ll be the first one to say, “Listen, this was my idea. I’m the guy who wrote the music. My bad. I wish it could have done better but we’ll move on to the next thing.”