Ew. No no no no no. Absolutely not!
I think it could really work as a girls name 
Personally, I’ve never seen [name]Jasper[/name] as all too masculine. [name]Gaspar[/name] always seemed very masculine to me.
A post before me mentioned that if girls take traditional boys names, then there won’t be any left for the girls. The reason most people are comfortable giving a girl a boys name is because it’s okay to be a boy. In society, there seems to be something shameful in a man being mistaken for a woman. I don’t think names should be “boys or girls”. I know that’s an idealistic world. Perhaps after girls take over all the boys names, boys will have to take girls names and everything will be equal. Then no one will pick on the boy named [name]Sue[/name].
Anyway, here are some alternatives:
Jasher (Hebrew; upright)
[name]Jasmine[/name]
Jaswinder (Sanskrit; [name]Indra[/name]'s thunderbolt)
[name]Aster[/name]
[name]Cooper[/name]
[name]Copper[/name]
[name]Esther[/name] nn. [name]Esti[/name]
[name]Harper[/name]
Hesper
[name]Juniper[/name]
[name]Piper[/name]
[name]Vesper[/name]
Whisper
[name]Winter[/name]
Nature names are neutral. [name]Jasper[/name] is traditionally male. She will be mistaken for a boy. Nothing wrong with that.
I was going to mention the name [name]Vesper[/name] also. The feel is similar to [name]Jasper[/name] but [name]Vesper[/name] is much more feminine to me. [name]Jasper[/name] is a great name but to me it goes to the boys. But to each his or her own. My sister plans on naming her daughter hypothetical daughter Wallice nick name [name]Wally[/name]. So it’s all how you feel about it.
Yes you can use it just make sure you spell it as [name]JASPER[/name] though. I think it will become more popular for girls.
rollo
I would not because she would forever be thought a boy on paper. If you [name]LOVE[/name] it she is your child so use it but just be prepared for lots of corrections before they meet her in person.
I love it you should use it for sure
I think it is awful on a girl. You can do whatever you want, but especially if your other daughter has a feminine name I would always assume a [name]Jasper[/name] on paper was a boy. It wouldn’t occur to me it could be a girl.
I don’t like it on a girl at all.
You can use whatever name for whatever gender, of course. Nobody can stop you, so I find it silly when people use that argument.
Would I like to be a girl called [name]Jasper[/name]? No. You’d be assumed to be a boy all. the. time. Life is hard enough to navigate, frankly.
Someone upthread mentioned a boy named [name]Ruby[/name]: that is just cruel, really. [name]Ruby[/name] is as girlish as [name]Jasper[/name] is boyish.
the argument that [name]Jasper[/name] is girly because it is a stine…have youn seen the stone? it is super manly. Dimonds and Rubies are ultra feminine and [name]Jasper[/name] is masculine. [name]Noone[/name] would want a [name]Jasper[/name] engagement ring Lol
Sure, you Can use it for a girl, its just obviously controversial.
Regarding [name]Ruby[/name] as a boys name I thought this might be of interest: Ruby Walsh - Wikipedia. He’s a famous Irish jockey.
Jasper is solely male here too. No one would imagine Jasper could be a girls name.
[name]Jasper[/name] is a boy name, there are lots of them here, and as Dearest said, it’s very close to [name]Jesper[/name] and [name]Casper[/name].
(I could see [name]Ruby[/name] on a boy, it’s so close to [name]Rudy[/name]!)
Where I live all the [name]Jamies[/name] I know are girls. More often than not, though, older people (college professors and co-workers) assume I’m a boy. It’s not that big of a deal. I usually just say “Nope, I’m a girl” and continue on with my life.
I’m not crazy about the name [name]Jasper[/name] for either gender. But I think that if your other daughter has more of a unisex name it could work.
The argument about it being a gemstone is kind of dumb, in my opinion. It’s been a name for many, many years–and always on boys. 9 out of 10 people who hear [name]Jasper[/name] are going to think of a boy’s name and not a gemstone.
I think [name]Jasper[/name] on a girl is spunky and strong. I’ve always loved it for a boy, but it can work for a girl.
Wait…people use [name]Evan[/name] for girls?