I’d like to find out if I’m a candidate to donate a kidney to a friend and apparently the first step is to find out my blood type. I can’t do it thru being a blood donor because I am told I would have to give a “full bag” and since I clot like crazy, not likely to happen. I’d go to a regular lab, except I can’t get them to tell me how much it would cost! Any other ideas?
Join the military and then read your ID card.
It’s probably listed in your medical records if you have any. Might be listed on your birth certificate…or your mother may know, if she’s available. I remember doing a blood typing excercise in high school biology years ago…maybe there are kits available online?
Yup…found via google, so buyer beware, but:
If you don’t mind me riding on the coattails of this thread, can I ask knowledgeable Dopers if it possible to know your blood type if you know that of both parents? My husband and I are both A+. Does this mean our son must be too, or are there other possibilities?
Here’s a home test for about $16.
http://www.amazon.com/Blood-Eldoncard-Determine-blood-minutes/dp/B000G33TM2
He’s either A or O. Check this out.
Hey, good question. I have no idea what my blood type is either.
I wonder how many people do in fact know this?
Being on a google roll tonight…(explains blood type genetic stuff)
I’m a little old (51) and not exactly in working order 
Not in my records or on my birth certificate and mother not available.
Wow, look at all of that! Thanks!
Huh, with all these choices, I wonder if a pharmacy would carry this?
My husband does, but he is naturalized so that might be why.
I just checked some of the major pharmacies websites and nothing showed up, so I doubt you’ll find the test at your neighborhood pharmacy. It’s probably not an item requested enough to bother stocking.
Become a blood donor.
The OP states that he can’t, due to clotting. I’ve had the blood clot up in the needle before the bag was full a time or two. Now I drink a lot of water the day or two before I donate. I can’t guarantee results, but so far it’s worked for me. I’m O neg and the blood bank is always after me.
While the A+A=O question has been answered, the positive and negative question hasn’t been addressed. Rh negative is recessive, therefore people with positive blood can produce children with negative blood.
So two A positives can have the following children:
A+ , A- , O+, or O-.
Apologies if I missed a link that mentioned that.
In Spain it’s the kind of test that’s done in some pharmacies (generally a pharmacy that checks for glucose will check cholesterol and blood type as well). Maybe there’s some in yoru area which offer that kind of service?
I’m AB+
Sort of rare-ish, and kind of inverse-universal. I can handle any type of blood, but only others with AB+ can have my blood.
Other than for blood donor purposes, where the notice goes out calling for “O” donors or similar, it’s not all that useful to know one’s blood type. It’s not a test we even run on 99.9% of our patients in a primary care setting, anyway.
If one needs a transfusion, blood typing and many, many other more sophisticated compatibility tests will be run to figure out what type of blood product to give the person at that particular time.
If you must know your type, go donate blood. You’ll get a nice card with your type and your rh factor on it.
That would be ‘universal recipient’ I believe.
O negative is properly ‘universal donor.’
There’s no truly universal blood type, just those two extremes, so you’re not inverted. Just… bloody selfish? 
I don’t think blood typing is always standard procedure for new babies. Or if it’s standard, it’s not required. It wasn’t on any of the paperwork for my daughters (both born outside hospitals), so I don’t know their blood type(s). My husband doesn’t know his, although there’s a record of it somewhere in his medical files since he’s received transfusions, so I can’t even narrow it down.
When my brother was born he was typed, apparently part of protocol. I remember because his blood type is not that of either of our parents, but the nurse was quick to explain that this is totally normal don’t worry blah blah blah. It seems some parents get very upset and start suspecting parentage when the types don’t match up.
I once asked my doc the same question. He advised me to go to the Red Cross, give blood, and then look at the donor card mailed to me a couple of weeks later.
I think he was just promoting blood donation.