Barrel units

The last conversion in the chain. A unit is not a volume until the calibration is named, so the calibration is a required field with no default.

Educational arithmetic only. Not medical advice and not a dosing protocol.

Enter the figures above.

One volume on all five barrels. Each figure is the volume multiplied by the calibration named in its column, and a cell says so where the draw is past what the barrel holds.
Volume	U-100, 1 mL	U-100, 0.5 mL	U-100, 0.3 mL	U-50, 0.5 mL	U-40, 1 mL
0.025 mL	2.5	2.5	2.5	1.25	1
0.05 mL	5	5	5	2.5	2
0.1 mL	10	10	10	5	4
0.2 mL	20	20	20	10	8
0.3 mL	30	30	30	15	12
0.5 mL	50	50	past the barrel	25	20

What this figure is not

This is educational arithmetic on figures entered by the reader. It is not medical advice, not a dosing protocol, and not a recommendation that anything be prepared, obtained or administered.

Nothing here states what quantity is appropriate for anyone, and there is no function in it that produces an amount to administer. A question about anyone’s health belongs with a licensed clinician who can examine the person asking.

Compounds of the kind this arithmetic is used on are largely research chemicals that are not approved by the FDA for human use. An exact calculation is not an accurate measurement: what is actually in a syringe depends on the preparation and the device, neither of which this page can see.

No qualified clinical reviewer is recorded against this site, and no credential is claimed anywhere on it. the full version.

Calibration and capacity are different numbers

Calibration is how many units fill a millilitre: 100, 50 or 40. Capacity is how much the barrel holds: 1 mL, 0.5 mL or 0.3 mL. A U-100 barrel can be any of those three capacities, all three read the same number for the same volume, and only one of them can take eighty units.

Which means a reading can be arithmetically correct and physically impossible. This worksheet flags that rather than printing a number the device cannot deliver.

Why there is no default calibration

U-100 is the most common calibration in most markets, and that is exactly what makes assuming it hazardous. The assumption is right often enough to go unchallenged and wrong by a factor of two or two and a half when it fails, and nothing about the answer would look different.

So the field starts unselected and the worksheet refuses to produce a reading without it. It is the only field on this site with that kind of friction.