I love [name]Harper[/name] for a boy! Honestly, it is super trendy for girls, but it’s still climbing in popularity for boys, and it looks like it’s the most popular it’s ever been (just like it is for [name]Avery[/name]! And I’m not too concerned about [name]Avery[/name] at all). I came across a little boy named [name]Harper[/name] on a TV show once, and I totally fell in love with it, I think once people actually meet a little boy named [name]Harper[/name] they’ll love him. 
If you look at the charts, it looks like [name]Harper[/name] on a boy is skyrocketing much more for boys than girls, it’s just shooting up the charts. It may not be as popular on a boy as a girl, but I definitely wouldn’t give [name]Harper[/name] up!
[name]Harper[/name] sounds like a boy’s name. There are a lot of more girly names for girls and I would suggest other girly name. A girl should go for a girls name.
Sorry, I would call it out for a boy.
Not to me, probably because my Prime Minister’s surname is [name]Harper[/name].
The stats southern_maple posted are important. They show that approximately 1.2% of all babies born in the US last year were named [name]Harper[/name], and that female Harpers were 11.5 times as common as male Harpers. That is to say, only 7% of Harpers are boys.
This means, beyond the shadow of a doubt, that the general public image of [name]Harper[/name] is female. Once that snowball gets rolling, it’s he’d to stop. I wold expect the %age of total Harpers who are male to decrease annually, but never go to zero.
It’s up to you how much this bothers you. your son would have a go-to reason to stave off teasing, the family name. But there still might be teasing, or at least a few raised eyebrows and smirks.
I don’t agree with occupational surnames being gendered.
Names like [name]Addison[/name]? Sure. Literal meaning “son of [name]Adam[/name].” That’s used on girls quite popularly, but I can see the argument it is inherently masculine.
[name]Harper[/name], [name]Mason[/name], [name]Carter[/name], [name]Piper[/name], [name]Archer[/name] - what is inherent more feminine about being a piper than a bricklayer? Nothing at all. Or, historically, construction workers have been male - but so have most professional musicians. Are we saying girls can have occupational names if the occupation is soft/pretty/the arts? And that boys can’t be named [name]Poet[/name] but they can be, what, barrel-makers? A girl might break a nail doing that…?
However I’m aware that plenty of people see nothing at all odd in saying [name]Madison[/name] is for girls and [name]Mason[/name] is for boys. I just don’t see any internal logic.
I don’t love the name [name]Harper[/name], though I do see it as a girl’s name.
I like [name]Archer[/name] for a boy though!!
I feel like [name]Harper[/name] is getting so popular for girls that I wouldn’t use it as a boy’s name. Tons of celebrities are using it and I know of at least two [name]Harper[/name] [name]Olivia[/name]'s in real life. That being said, depending on your feelings about popularity of a name, you could use it for a girl. Also, I think [name]Archer[/name] is a really cool boy name.