Ester and pre-mixed oil calculator
For oils sold at a labeled strength: testosterone, estradiol and the rest. Put in the mg/mL and your weekly dose, and get the draw on the syringe in your hand, how long the vial lasts, and what it costs a week.
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on the label
Enter your weekly dose above.
The bottle we know. The dose is yours; we don’t guess it.
Injections per vial, days per vial and cost appear with your weekly dose.
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The link carries the numbers. Paste it in a thread and it opens filled in, no account needed.
Enter your weekly dose to get a linkWhy oil gets its own calculator
A pre-mixed vial has nothing to reconstitute. The concentration is printed on the label, so the whole calculation is one division: the amount per injection over the milligrams per milliliter.
What is easy to get wrong is the reading. On a U-100 insulin syringe a unit is a volume, 0.01 mL, not an amount of hormone. At 200 mg/mL each unit holds 2 mg.
When it leaves the insulin syringe
An insulin syringe holds 1 mL at most. Past that the calculator stops talking about barrel marks and says so: above 1 mL is the territory of a 3 mL luer syringe, and above 3 mL is more than one injection or a more concentrated vial.
Pre-mixed oil questions
- How do I work out how much oil to draw?
- Divide your weekly amount by the number of injections in a week to get the amount per injection. Divide that by the concentration on the label (mg/mL) to get milliliters. On a U-100 insulin syringe every 0.01 mL is one unit, so multiply the milliliters by 100 for units. The calculator shows each step under Show work.
- How many milligrams are in one unit on an insulin syringe?
- A unit on a U-100 syringe is a volume, 0.01 mL, so what it holds depends on the oil. At 200 mg/mL one unit is 2 mg; at 250 mg/mL it is 2.5 mg; at 20 mg/mL it is 0.2 mg. The calculator prints this under the concentration.
- Why does it say my draw is between marks?
- Insulin syringes are printed at fixed steps: every half unit on a 0.3 mL barrel, every unit on a 0.5 mL, every two units on a 1 mL. A draw that falls between two lines can only be estimated. The calculator names the nearest mark, how far off it is in percent, and a barrel that marks the draw exactly when one exists.
- What happens when the draw is more than 1 mL?
- An insulin syringe holds 1 mL at most, so above that the calculator stops talking about barrel marks. Most people use a 3 mL luer syringe at that volume. Above 3 mL it says to split the volume across injections or use a more concentrated vial.
- How long will a vial last, and what does it cost per week?
- Injections per vial is the vial volume divided by the draw, rounded down, since a partial draw isn't an injection. Days per vial follows from your schedule. Enter what you paid for the vial and it divides that across the injections to give a cost per injection and per week.
- Does this calculator recommend a dose?
- No. It does arithmetic on numbers you enter. Picking a compound fills in the concentration printed on its label and nothing else; the weekly dose field starts empty and stays yours. Where a drug label or a trial states a fixed dose for that compound, it is listed under the field with a link to the text that states it, and tapping it enters it. For medical decisions, consult a qualified healthcare professional.
For informational purposes only. This tool performs mathematical calculations on numbers you enter and does not provide medical advice. Consult a healthcare professional for medical decisions.