Enter what's in the vial, the liquid added and an amount. See the concentration, the volume and where it falls on your syringe.
Stackr keeps a record of what you have, logs what you take, and reminds you before you run out.
Download Stackr FreeReconstituting means adding liquid, such as bacteriostatic water (BAC water), to a freeze-dried powder so it becomes a solution. This page does the arithmetic that follows: given the amount in the vial, the liquid added and an amount you type, it shows the concentration, the volume that contains that amount, and where that volume falls on the syringe type you selected.
The arithmetic is simple, but converting between milligrams, micrograms, milliliters and syringe units is where slips happen. The calculator shows each step so the numbers can be checked. It does not suggest or recommend any amount.
Example arithmetic: a vial labeled 10 mg (10,000 mcg) with 2 ml of liquid added has a concentration of 5,000 mcg/ml. An amount of 250 mcg is contained in 0.05 ml, which falls at the 5 mark on a U100 syringe.
Bacteriostatic water is sterile water containing 0.9% benzyl alcohol as a preservative, which suppresses bacterial growth in a multi-use vial. Plain sterile water has no preservative. Which liquid to use, and how much, is set by your product's labeling and your healthcare professional, not by this calculator.
| Syringe Type | Units per ml | 1 unit equals | Markings |
|---|---|---|---|
| U100 | 100 | 0.01 ml | Fine graduations for small volumes. Common in the US. |
| U40 | 40 | 0.025 ml | Less common. Each unit is 2.5× a U100 unit. |
| Standard mL | — | — | Marked directly in ml; no unit conversion. |
A U40 unit is 2.5× larger than a U100 unit, so the same number of units is a very different volume on each. The result above is only correct for the syringe type selected.
Storage temperature, how long a mixed vial stays usable, and when to discard it vary by product. Follow your product's labeling. Sterile solutions should be clear; cloudiness, discoloration or particles are a reason to check with the supplier or your healthcare professional.
The concentration is the vial contents divided by the liquid added. The volume is the amount you entered divided by that concentration. On a U100 syringe the mark is the volume in ml × 100; on a U40 syringe, × 40.
No. Stackr does not recommend amounts for anything. The calculator converts numbers you type in, and nothing else. Check every result against your product's labeling and your healthcare professional.
That comes from your product's labeling or your healthcare professional, not from this calculator. Enter the volume that was actually added, and the calculator shows the resulting concentration.
U100 is marked so that 100 units = 1 ml. U40 is 40 units per ml, so each unit is 2.5× larger. Reading a U40 as if it were a U100 gives the wrong volume, so the calculator asks which type you have.
Choose IU as the unit and enter the vial contents and the amount in IU. IU cannot be converted to mg without product-specific information, so the calculator keeps everything in IU and Pre-Mixed mode works in mg or mcg only.
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Keep track of your supply. The Stackr iOS app records what you have and reminds you before you run out.
Download Stackr FreeThis calculator is an arithmetic tool for reference only. It is not intended to provide medical advice, diagnosis, or treatment, and Stackr does not recommend amounts for any product. Always check against your product's labeling and consult a qualified healthcare professional.