Free tool
Volume and unit converter
At a known concentration, mass and volume are interchangeable. This converts between them and expresses the result in the graduations on a 100-unit syringe barrel.
Your solution, and the mass you are looking for
Concentration first, then the mass you want to find in it.
Your answer
Where that mass falls on the barrel graduations.
Show the other figures
- Graduations on a 100-unit barrel
- — units
- Proportion of the barrel
- — %
- Micrograms per millilitre
- — µg/mL
Arithmetic only. This tool converts between mass, volume and concentration for laboratory preparation and dilution planning. It is not dosing guidance, and nothing here is a therapeutic claim. All materials are supplied for in-vitro laboratory research use only.
How the arithmetic works
volume = mass ÷ concentration
A so-called insulin syringe is graduated in units rather than millilitres, where 100 units corresponds to 1 mL on a 1 mL barrel. The graduations are a volume scale, not a mass scale — the same unit mark corresponds to a different mass at every concentration, which is why the concentration has to be established before the scale means anything.
The proportion-of-barrel figure is a practical check. A volume below roughly five percent of the barrel is hard to measure reproducibly; if that is where you land, reconstituting at a lower concentration next time will give you a volume you can actually read.
Frequently asked
How many units is 1 mL?
On a 100-unit syringe barrel, 100 units corresponds to 1 mL. On a 0.5 mL barrel marked to 50 units, each unit is still 0.01 mL.
Do syringe units measure mass?
No. They are a volume scale. The mass at a given unit mark depends entirely on the concentration of the solution, which is why concentration must be established first.
Why is my volume so small?
Because the solution is concentrated. Volumes below about five percent of the barrel are difficult to measure reproducibly — reconstituting with more diluent next time gives a larger, more readable volume for the same mass.