Most adults average about 5 liters of blood volume. How does dwarfism effect that? Would they be more comparable to blood volume in kids? I haven’t found an average for them. I’d guess it varies depending on a kid’s age.
You can use this to calculate blood volume based on human development stages and weight: Estimated Blood Volume
Need answer fast?
No hurry, we won’t make the blood pies until next week. 
I just wondered how much body size determined blood volume. Small container should hold less.
The calculator link posted earlier seems way high. 190lb man calculates to 6.46L but many sources indicates the average is 5 to 5.5
How 'bout on the kid’s size?
Surely blood volume would be closely tied to the volume of flesh.
What was taught me was 70 ml/kg, which converts to 32 ml/lb, which converts to about 1 pint/15 pounds. Brand new babies have a little more blood/weight, but they even out by the time they’re ankle biters.
The minimum weight for donating blood (in the U.S.) is 110 pounds, and, yes, the amount of blood is mostly determined by the weight:
Normal blood volume in people with healthy blood physiology is best normalized against lean body mass, and not total weight.
Fat people don’t have as much blood (total volume or RBC mass) per kilogram as do thinner ones.
The range is quite marked; a really fat guy might have a blood volume of about 50 cc/kg, while a really skinny one might be closer to 80 cc/kg.
I doubt height has as much to do with blood volume as does the degree of obesity, at least in adults.