How can you tell the difference between a boy and girl parakeet/budgie?

I've had over 7 parakeets over time, you know the small ones that are about 3 inches tall, some blue, some green others white or yellow. How can you tell a boy from a girl, because I have one right now but I don't really know how to tell what sex it is. I also would love to know how long theyre suppose to live, this one is about 3 or 4 years. Thanks in advance to all answers

Easy :)Girl- flaky brown/pinkish cereBoy- smooth blue/purplish cereThe cere is the patch of skin above the beak, where the nostril is.

Hi,Telling a budgie's gender by appearance is very easy and mostly very accurate. You won't need to spend money on DNA tests, blood tests or feather samples, and simply look at the budgie's cere. If you don't know what the cere is, it is the fleshy part above its beak, where their nostrils are. Also, you cannot tell gender by cere color until your budgie is mature, meaning it has passed 6-12 months of age. A mature female budgie's cere will be beige/brown, sometimes with hints of pink or white, and usually more flaky and crusty. A male's cere will be blue/purple, and very smooth. See if this helps if you are confused. The first picture is of a male, the second is a female:http://www.parrot-bird.com/budgerigar-100.jpghttp://www.pet-informed-veterinary-advice-online.com/images/female-parakeet-budgie.jpgFor how long they live, a healthy budgie can live anywhere between 10-15 years. Occasionally recorded to be a bit higher.Good luck with your budgies!