What is HCG and why is it labeled in IU?
An HCG reconstitution calculator works a little differently from a peptide calculator, because HCG is labeled in international units instead of milligrams. HCG stands for human chorionic gonadotropin, a glycoprotein hormone built from two protein chains, an alpha subunit and a beta subunit, with sugar groups attached. It is much larger and more complex than the short peptides elsewhere in this library.
Because a protein like this is standardized by its biological activity rather than its weight, the vial states a number of IU, such as 5,000 IU or 10,000 IU. IU and mg measure different things and cannot be converted with a simple factor, so this calculator keeps everything in IU: IU on the vial, IU for the amount, and IU per mL for the concentration.
How much BAC water for an HCG 5000 IU or 10000 IU vial?
An hcg 5000 iu vial and an hcg 10000 iu vial are the two sizes people search for most. The vial’s IU never changes; the liquid you add decides how many IU sit in each unit on a U-100 syringe. The chart below shows IU per unit for several water volumes.
| BAC water | 5,000 IU vial | 10,000 IU vial |
|---|---|---|
| 1 mL | 50 IU/unit 5,000 IU/mL | 100 IU/unit 10,000 IU/mL |
| 2 mL | 25 IU/unit 2,500 IU/mL | 50 IU/unit 5,000 IU/mL |
| 5 mL | 10 IU/unit 1,000 IU/mL | 20 IU/unit 2,000 IU/mL |
| 10 mL | 5 IU/unit 500 IU/mL | 10 IU/unit 1,000 IU/mL |
Each cell shows IU per unit on a U-100 syringe (100 units = 1 mL) and the resulting concentration.
More water spreads the same IU across more liquid, so each unit holds less. The larger vial at twice the water matches the smaller vial at half the water, because the concentration comes out the same. The mixing volume printed on the product labeling is the one that applies to that product; this chart only shows how the arithmetic changes. For a closer look at the volumes BAC water comes in, see the guide to bacteriostatic water vial sizes.
Worked example: HCG mixing math in syringe units
The calculator runs the same three steps as every other page, just in IU. Vial IU ÷ water mL gives IU per mL. The IU amount you enter ÷ IU per mL gives the volume in mL. Volume in mL × 100 gives U-100 units. For example, if the amount you already have is 250 IU and the vial is 5,000 IU with 5 mL of water added:
The math: 5,000 IU ÷ 5 mL = 1,000 IU/mL, which is 10 IU per unit. 250 IU ÷ 1,000 IU/mL = 0.25 mL = 25 units on a U-100 syringe.
Now run the same arbitrary amount through a 10,000 IU vial with twice the water:
The math: 10,000 IU ÷ 10 mL = 1,000 IU/mL, which is 10 IU per unit. 250 IU ÷ 1,000 IU/mL = 0.25 mL = 25 units on a U-100 syringe.
The two results match because the concentration is identical. Neither amount is a suggestion; they are round figures picked to make the arithmetic easy to follow. Since 100 units = 1 mL on a U-100 syringe, you can convert syringe units to mL in either direction to double-check a reading.
HCG calculator dosage: what the numbers mean
Searches for an hcg calculator dosage tool usually come from someone who already has an IU figure and wants to see where it falls on a syringe. That is the whole job of this page. The calculator converts the IU you enter into mL and units based on your vial and water volume. It does not choose, suggest or check a dose, a schedule or a frequency.
Two checks catch most errors. First, make sure the vial IU and the amount are both in IU; the calculator will not mix IU with mg or mcg. Second, confirm the water volume matches what actually went into the vial. If a result still looks wrong, the steps to check calculator math by hand apply to IU exactly as they do to mg.
HCG reconstitution and mixing instructions on the label
HCG reconstitution details come from the product labeling, not from a calculator. FDA-approved chorionic gonadotropin products are packaged with a specific diluent named in their labeling, along with the volume and the storage conditions after mixing. Research-labeled vials vary: some suppliers specify bacteriostatic water, and others specify sterile water. Any hcg mixing instructions you rely on should come from the label of the exact product in hand and a qualified professional.
- Record the water volume and the mixing date on the vial.
- Bacteriostatic water contains 0.9% benzyl alcohol, which slows some bacterial growth but does not sterilize. For background, see what bacteriostatic water is.
- An opened multi-dose vial is commonly dated and discarded within 28 days unless the manufacturer specifies a different date.
Approved HCG drugs vs research-labeled vials
Chorionic gonadotropin products such as Novarel and Pregnyl are FDA-approved prescription drugs with their own approved labeling. HCG vials sold online labeled for research use are not those approved products. They carry no approved labeling, and their identity, potency and sterility depend on the supplier.
A correct calculation cannot confirm what is in a vial or whether it is suitable for anything. It only shows how the IU on the label relate to the water you added and the marks on your syringe. To compare other labeled calculators, open the peptide library.
HCG FAQ
Why is HCG measured in IU instead of mg?
HCG is a glycoprotein hormone standardized by biological activity, so vials state international units. IU and mg measure different things, and the calculator keeps all HCG values in IU.
How much water goes in an HCG 5000 IU vial?
The product labeling specifies the diluent and volume for that product. The chart on this page shows how IU per syringe unit changes with different water volumes so you can see the arithmetic behind any volume.
Is a 10000 IU vial with 10 mL the same as a 5000 IU vial with 5 mL?
Yes. Both work out to the same IU per mL, so the same IU amount takes the same number of units on a U-100 syringe.
Is this an HCG dosage calculator?
It converts an IU amount you already have into mL and U-100 syringe units. It does not recommend or check any dose, schedule or frequency.
Are research HCG vials the same as Pregnyl or Novarel?
No. Pregnyl and Novarel are FDA-approved chorionic gonadotropin products with approved labeling. Research-labeled vials are not those products.