mg, mL and syringe unit converter
A milligram is an amount of drug. A mark on an insulin syringe is an amount of liquid. The two only line up once you know how concentrated the liquid is, which is why every answer below waits for that number and prints it back to you with the result.
Nothing is filled in for you, no dose is suggested, and no schedule is proposed. It converts what you type.
Convert an amount
The mg in each mL, as printed on the vial or the pharmacy label.
From your own prescription label. Nothing is filled in for you.
Enter the strength first — the same milligrams read as a different number of units at a different strength.
The arithmetic
Enter a strength and an amount, both above zero. A unit mark on a syringe measures volume, not drug, so there is no answer at all until the strength is known.
Assumes a U-100 insulin syringe: 100 units is 1 mL, so 1 unit is 0.01 mL. A U-40 or U-500 syringe is marked on a different scale and none of these unit figures applies to it.
Assumes the liquid is at the strength entered above and evenly mixed, and that the strength you entered is the one printed on your vial or given by whoever dispensed it.
Assumes a barrel marked in whole units with a half-unit line between them, so the drawable reading is the nearest 0.5 units. The exact figure is shown beside it whenever the two differ.
Doses in a vial
The total in the vial divided by the amount drawn each time, counted in whole doses — a part-dose left in the bottom is not a dose. The schedule is yours to enter; this does not propose one.
As printed on the vial label.
From your own prescription label.
The number your own prescription calls for.
What that vial holds
Enter all three numbers, each above zero. Nothing is filled in for you.
Assumes every dose is drawn at the strength entered, that nothing is lost to priming the needle or to what stays in the hub, and that the number of injections is the one on your own prescription.
Pen clicks are not a conversion
Click charts circulate for every dial pen on the market, and none of them is arithmetic. How many detents a dial makes between one dose and the next is a mechanical property of that one device, stated in that device’s own instructions or nowhere. There is no clicks-per-milligram rule to carry from one product to another, so this tool converts milligrams, milliliters and syringe units — quantities that have definitions — and computes no clicks.
On the pen those charts are most often written about, the instructions are explicit. The Ozempic pen Instructions for Use, revised June 2026, say:
- You will hear a “click” every time you turn the dose selector. Do not set the dose by counting the number of clicks you hear.
- The dose selector clicks differently when turned forward or backward. Do not count the pen clicks.
- Always use the dose counter and the dose pointer to see how many mg you select.
The dose counter on the pen is the number to read. A chart that turns clicks into milligrams is asking you to do the one thing the device’s own instructions tell you not to.
Source: Ozempic prescribing information and Instructions for Use
What this arithmetic applies to
Any liquid whose strength you know. The converter names no compound and needs none: milligrams, milliliters and syringe units are defined quantities that belong to no product. On this site the peptides a licensed seller may prescribe as a compounded injection are semaglutide, tirzepatide, liraglutide, sermorelin, NAD+, glutathione, PT-141 (bremelanotide).
MOTS-c, BPC-157, kisspeptin, CJC-1295, ipamorelin, epitalon, DSIP, TB-500, retatrutide, MK-677, thymosin alpha-1, KPV, melanotan II, AOD-9604, semax, selank, SS-31, LL-37 and 5-Amino-1MQ are covered as research only. MOTS-c, BPC-157, CJC-1295, epitalon, DSIP, TB-500, retatrutide, KPV, melanotan II, AOD-9604, semax, selank, SS-31, LL-37 and 5-Amino-1MQ are on no compounding list; kisspeptin and MK-677 are in FDA's 503A Category 2 for safety risks; ipamorelin is in FDA's 503B Category 2 for safety risks; thymosin alpha-1 is nominated for 503B compounding without adequate support. No pharmacy may lawfully compound any of them today, so this site publishes no dose, no schedule and no seller for them. A converter that will happily divide any two numbers is not a way around that: the number it needs still has to come from a prescription that exists.
If you have not mixed the vial yet, the reconstitution and dose calculator starts from the vial and the water instead, and how to reconstitute peptides covers the mixing and storing step by step.
Frequently asked questions
- How many units is 2.5 mg?
- It depends entirely on how concentrated the liquid is, because a unit mark on an insulin syringe measures volume, not drug. A U-100 syringe holds 100 units in 1 mL. At 2.5 mg/mL, 2.5 mg is 1 mL, which is 100 units — a full barrel. At 5 mg/mL the same 2.5 mg is half that, 50 units. Any page that answers this with one number has assumed a strength without saying so.
- Is 0.25 mg always 25 units?
- Only at 1 mg/mL. The rule circulates as though it were a property of the drug, but it is a property of that one strength. Draw 0.25 mg from a liquid at 2.5 mg/mL and the reading is 10 units, not 25.
- How do you turn milligrams into milliliters?
- Divide the amount by the strength of the liquid. Two milligrams of a liquid at 4 mg/mL is 0.5 mL. The strength has to come from your own vial or pharmacy label; there is no standard strength to assume.
- Why does the reading sometimes differ from the exact figure?
- A standard barrel is marked in whole units with a half-unit line between them, so the finest reading is 0.5 units. When the exact figure falls between two lines, the tool shows the nearest line, prints the exact figure beside it, and says what that line would actually deliver.
- Can it tell me how many clicks to dial on a pen?
- No. A click count is a mechanical property of one particular pen, stated in that pen's own instructions or not at all, and there is no clicks-per-milligram rule that carries across products. The Ozempic pen instructions, revised June 2026, go further: "You will hear a “click” every time you turn the dose selector. Do not set the dose by counting the number of clicks you hear."
- Can I use this for a research-only peptide?
- The arithmetic does not know what is in the vial — a milligram is a milligram. What it cannot supply is the number to convert. MOTS-c, BPC-157, CJC-1295, epitalon, DSIP, TB-500, retatrutide, KPV, melanotan II, AOD-9604, semax, selank, SS-31, LL-37 and 5-Amino-1MQ are on no compounding list; kisspeptin and MK-677 are in FDA's 503A Category 2 for safety risks; ipamorelin is in FDA's 503B Category 2 for safety risks; thymosin alpha-1 is nominated for 503B compounding without adequate support. No pharmacy may lawfully compound any of them today, so there is no prescription label to read a dose from, and this site publishes no dose and no seller for them.
- Does a U-40 or U-500 syringe read the same?
- No. "U-100" names the scale: 100 units to the milliliter. A U-40 barrel puts 40 units in that same milliliter and a U-500 puts 500, so the same volume reads as a completely different number. Every unit figure on this page is a U-100 figure.