Free calculator · No sign-up

Syringe unit converter

Insulin syringe markings measure volume, and how much volume a single unit represents depends on the barrel's calibration: 0.01 mL on U-100, 0.02 mL on U-50, and 0.025 mL on U-40. This tool converts between units, millilitres and — if you supply a concentration — an amount in mg or mcg.

Syringe calibration

Read it off the barrel.

Units on the syringe

That is a volume of

0.1 mL

One unit equals

0.01 mL

Optional — convert to an amount

If you know the concentration of your solution — from your own reconstitution, or printed on a pharmacy-compounded vial — enter it to see what that volume contains.

Concentration

mcg/mL

Amount in that volume

250 mcg

Same reading, three barrels

Calibration	1 unit	Your reading

The three calibrations

Type	Units per mL	1 unit	10 units	Where you meet it
U-100	100	0.01 mL	0.1 mL	The standard human insulin syringe
U-50	50	0.02 mL	0.2 mL	Less common; wider-spaced marks
U-40	40	0.025 mL	0.25 mL	Veterinary use in some countries

Check the barrel print rather than the box, and rather than assumption. See reading an insulin syringe for how to read the increments correctly once you know the calibration.

Adding a concentration

Supply a concentration and the tool also converts to an amount. This is the case that applies to a compounded GLP-1 vial, where the pharmacy states a concentration and you draw a volume yourself, and to any research peptide vial you have already reconstituted.

Frequently asked questions

How many mL is 1 unit on an insulin syringe?

On a U-100 syringe, one unit is 0.01 mL. On U-50 it is 0.02 mL, and on U-40 it is 0.025 mL. The calibration is printed on the barrel and determines everything.

Is a 0.3 mL syringe different from a 1 mL syringe?

Only in total capacity and readability. On both, if they are U-100, one unit is 0.01 mL. The smaller barrel spreads fewer units over the same physical length, which makes small volumes considerably easier to read accurately.

What happens if I use the wrong syringe calibration?

You draw a different volume than intended, with nothing about the process feeling different. Reading '10' on a U-40 syringe gives 0.25 mL rather than the 0.1 mL you would get on U-100 — two and a half times as much.

Reading an insulin syringeIncrements, gauges and technique.Peptide unit converterFull mass ↔ volume conversion.Compounded GLP-1Where syringes meet GLP-1.All toolsThe full calculator index.

Stop recalculating this every time

PepCycle stores each vial once — mass, diluent volume, concentration — and converts automatically for every entry after that, in both directions, including entries you backdate.

Download on the App Store Or try the free calculators

Free to download · No account required · Price shown before you enter anything personal

Last reviewed July 22, 2026. All calculations run in your browser; no values are transmitted or stored.