Does anyone know what blood type Dumbledore was?
When you say Blood type, do you mean blood group or blood status? If you mean blood group, then as Neil said you can make him anything.
Lol, I'm A+ and I'm top of my class tooPersonally, I'd make him A+, proving that he's top of the class at everything.
If you mean blood status, then I asume he's a Pureblood (or maybe Half-blood). His parents were both magical, so he's definitely not a Muggleborn. I personally don't think he's half-blood though. If I were you I'd make him a Pureblood.
EDIT: Oh yes, he was a Half-blood. Thank you, Maple!
In DH, it is said that Kendra Dumbledore is Muggleborn, but that she pretended not to, thus making Dumbledore a half-blood.
Well, Muriel does say in DH that Kendra was a Muggleborn, but I personally doubt that. She may have been a Halfblood, though, making her children Halfbloods as well.
Kendra was a Muggleborn, not totally sure why you doubt that.
This is from Wiki
Anyway, even if she was a half blood, Albus, Aberforth and Ariana would still be classed as half bloods as there is some Muggle blood in their ancestry. For a family like the Blacks, any Muggle ancestor would be disgraceful. For a family like the Malfoys, however, a half blood in the family isn't necessarily bad. (See Pottermore)Muriel claimed her to be Muggle-born and that she attempted to hide that fact. Doge, although he stated that she did nothing of the sort, did not contradict the claim about her heritage
I agree with half-blood - somebody in the books (I can't remember who) said that technically, almost anyone is a half-blood, as practically everyone has some Muggle ancestry. So even if Kendra only had one Muggle parent, and Muriel got the Muggleborn thing from Skeeter's book, it would still make Dumbledore a half-blood.
And my mum and I are O- and O+ respectively and were both very much top-of-the-class people. It would still be cute to have Dumbledore as an A+, though, if somebody for some reason needs his blood type.
For his blood type, it would be O+ since he's a wizard! Sorry, not on topic :\
We also know that he had an aunt named Honoria, so you might want to look her up on any Potter sites.