Dose Calculator

What the Dose Calculator does

This is a unit-conversion calculator for compounded hormonal medications. Compounded drugs are prescribed in milligrams (mg) but measured in a syringe in milliliters (mL), and the two are not the same thing — the relationship depends entirely on how concentrated the vial is. The tool takes the dose your prescriber wrote in milligrams and converts it into the volume you would actually draw, plus the equivalent mark on a standard U-100 insulin syringe.

It covers five specific concentrations that you select from a dropdown: compounded semaglutide at 2.5 mg/mL and at 5 mg/mL, compounded tirzepatide at 10 mg/mL and at 15 mg/mL, and compounded progesterone at 100 mg/mL. You then type your prescribed dose in milligrams and the result updates immediately. There are no other inputs.

The arithmetic is fixed and transparent. Volume in mL equals your dose in mg divided by the vial's concentration in mg/mL. The syringe reading is that volume multiplied by 100, because a U-100 syringe holds 100 units per milliliter. For example, a 0.25 mg dose of semaglutide from a 2.5 mg/mL vial is 0.1 mL, which reads as 10 units on a U-100 syringe.

It is worth being clear about what this tool does not do, despite the broader framing that appears elsewhere on the page. It does not recommend a dose, and it does not ask for your weight, age, or reason for taking the medication. It does not build a titration schedule or tell you whether a dose is safe. It converts a number you already have into a different unit.

How to read your result

Pick the medication and concentration that matches your vial from the dropdown, then enter your prescribed dose in milligrams. Read the concentration off your own pharmacy label — a 2.5 mg/mL vial and a 5 mg/mL vial of the same drug produce very different draw volumes for the identical dose, so choosing the wrong one halves or doubles the answer.

The tool returns two numbers. 'Draw' is the volume in milliliters, rounded to two decimal places. 'U-100 syringe units' is that same volume expressed on an insulin syringe, rounded to the nearest whole unit. Both describe the same amount of liquid; the units line simply exists because most people injecting compounded medication use a U-100 syringe rather than reading tiny milliliter gradations.

Treat the output as a cross-check, not an instruction. If the number here disagrees with what your prescriber or pharmacy label says, the label wins — stop and ask them. The most common source of a mismatch is a concentration that differs from the five hardcoded here. If you want to weigh providers or refill options, you can compare providers elsewhere on the site, but the dose itself always comes from your clinician.

What the result is based on

Every result is plain arithmetic on two numbers you supply: your dose in milligrams and the vial concentration you pick from the list. Volume (mL) = dose (mg) / concentration (mg/mL). Syringe reading (units) = volume (mL) x 100, using the U-100 standard of 100 units per milliliter. There is no model, no dataset, no personalization, and nothing learned — the same inputs always produce the same output.

The five concentrations offered are fixed in the tool's code: semaglutide 2.5 and 5 mg/mL, tirzepatide 10 and 15 mg/mL, and progesterone 100 mg/mL. These are the only options; the calculator has no way to represent any other strength.

What it cannot tell you

• It only knows five concentrations. If your compounded vial is any other strength, none of the dropdown options match and the conversion will be wrong. Always confirm the mg/mL printed on your own label first.
• It assumes a U-100 syringe (100 units per mL). If you have a U-40 or any other syringe, the units figure does not apply, though the milliliter figure still does.
• It does not judge whether your dose is correct, safe, or appropriate for you. It has no input for weight, age, kidney function, other medications, or your reason for treatment, so it cannot flag a dose that is too high or a titration step that is being skipped.
• Results are rounded: milliliters to two decimals and units to the nearest whole number. For very small doses these rounding steps can shift the reading slightly, so a precise draw should follow your prescriber's stated volume.
• Compounded medication concentrations are set by the individual pharmacy and can change between vials or refills. A number that was right last month may not be right for a new vial at a different strength.
• It performs no safety or interaction checking and stores nothing about you. It is an educational reference, not a diagnosis, prescription, or substitute for your prescriber or pharmacist.