Tools / 10 mg vial

10 mg vial: how much water and how many units

How strong a 10 mg vial is after mixing, how many units each dose is on a U-100 syringe, and how many doses it holds. Pick your water amount and read across.

With 2 mL: 10 mg + 2 mL water = 5 mg/mL. Each unit holds 50 mcg, so 500 mcg is the 10-unit line.

[01] 10 mg vial
Powder plus water you add.

The mg printed on the vial label.

mg

Bacteriostatic (bac) water, in mL.

mL

Check whether it says mcg or mg. They differ by 1,000 times.

mcg
Which syringe?

It's printed on the packet: 0.3, 0.5 or 1 mL.

10 mg vial + 2 mL water → 500 mcg dose

Fill your syringe to

10units

The 10 line on a 1 mL syringe, which is 0.1 mL.

0102030405060708090100
Strength after mixing
5 mg/mL
Each unit holds
50 mcg
Doses in this vial
20
Show the math
  1. 10 mg × 1,000 = 10,000 mcg in the vial
  2. 10,000 mcg ÷ 2 mL = 5,000 mcg/mL
  3. 500 mcg ÷ 5,000 mcg/mL = 0.1 mL
  4. 0.1 mL × 100 units/mL = 10 units

Not what you expected? Check the numbers above, and confirm with your prescriber or pharmacist before you inject.

Checked November 8, 2026 by the PeptideTracker editorial team · This tool does the math only. It doesn't recommend a dose.

[02] Strength

How strong is a 10 mg vial after mixing?

A 10 mg vial mixed with 2 mL of bac water is 5 mg/mL, so each unit on a U-100 insulin syringe (0.01 mL) holds 50 mcg. More water makes each unit weaker.

10 mg vial: strength by water added (U-100 syringe)
Water addedStrengthEach unit holds
1 mL10 mg/mL100 mcg
2 mL5 mg/mL50 mcg
3 mL3.333 mg/mL33.33 mcg

[03] Units

How many units is each dose from a 10 mg vial?

With 2 mL of water, 500 mcg is 10 units on a U-100 syringe. The table shows example doses across water amounts. These are examples for the math, not recommended doses.

Units to draw from a 10 mg vial (U-100 syringe). Over 100 units won't fit a 1 mL syringe.
Dose1 mL water2 mL water3 mL water
250 mcg2.5 units5 units7.5 units
500 mcg5 units10 units15 units
1 mg10 units20 units30 units
2.5 mg25 units50 units75 units

[04] Doses per vial

How many doses are in a 10 mg vial?

The water doesn't change this. A 10 mg vial holds 10,000 mcg in total, so the number of doses depends only on the dose size.

Full doses in a 10 mg vial
DoseFull dosesLeft over
250 mcg40none
500 mcg20none
1 mg10none
2.5 mg4none

[05] Round lines

Water that puts 500 mcg on a round line (10 mg vial)

To land 500 mcg on a round line, add 2 mL: each dose is then the 10-unit line on a 1 mL syringe. Use the bac water planner to check your own dose, and read how much bac water to add for what changes with more or less water.

Other sizes: 2 mg · 5 mg · 15 mg · 20 mg · 30 mg · 50 mg

[06] Questions

Questions

How much bac water do I add to a 10 mg vial?

Any amount works for the math. 2 mL is common: it makes the vial 5 mg/mL, so each unit holds 50 mcg. More water spreads each dose over more units, which makes small doses easier to measure.

How many units is 500 mcg from a 10 mg vial?

With 2 mL of water it's 10 units on a U-100 syringe. With 1 mL it's 5 units, and with 3 mL it's 15 units.

How many 500 mcg doses are in a 10 mg vial?

20 full doses. The water you add doesn't change that.

Spotted a mistake or something out of date? Tell us. We aim to fix factual errors within two working days.

[07] Read next

Guides that go with this calculator