Calculators / HCG

HCG reconstitution calculator

Enter your vial size, bacteriostatic water, and target dose — get the concentration, the exact U-100 syringe draw, and how many doses the vial holds. No account, no vendor ties, numbers never leave your browser.

CONCENTRATION
5 mg/mL
YOUR DRAW (U-100)
10 units
DOSES IN VIAL
20
0102030405060708090100

How the math works

Three formulas, checked twice — the same engine that powers the Zyra Labs app:

Worked example: 10 mg HCG + 2 mL water = 5 mg/mL. A 500 mcg dose is then 500 mcg ÷ 5 mg/mL = 0.1 mL = 10 units on a U-100 insulin syringe.

HCG quick facts

Half-life≈ 33 h
Typical route (published research)SubQ · 2×/week
Common vial sizes5 mg · 10 mg

Source: hCG pharmacokinetic literature (see monograph)

See also: HCG half-life & clearance curve · HCG dose charts (mg → units)

Frequently asked

How much BAC water should I add to a 10 mg HCG vial?

There is no single correct amount — the water volume sets the concentration, not the dose. Adding 2 mL to 10 mg gives 5 mg/mL, which puts a 500 mcg draw at 10 units on a U-100 insulin syringe. More water = larger, easier-to-measure draws; less water = smaller draws.

How many units is 500 mcg of HCG?

It depends entirely on your concentration. At 5 mg/mL (10 mg + 2 mL), 500 mcg is 10 units on a U-100 syringe. Use the calculator above with your own vial and water volumes.

What is the half-life of HCG?

HCG's reported half-life is ≈ 33 h. See our cited half-life reference for the decay curve and clearance math.

Is this medical advice?

No. This calculator performs general arithmetic on values you enter, for research and educational purposes. It never recommends doses and we never answer sourcing questions.

Guides for HCG

Track the whole protocol, not just one draw

The Zyra Labs app logs doses, schedules reminders, estimates medication levels from published half-lives, and keeps everything on your device. Free to start.

Open Zyra Labs

Zyra Labs is a research and educational utility. Nothing on this page is medical advice, a dosing recommendation, or an endorsement of any compound. We never sell or source compounds and refuse sourcing questions. Consult a qualified clinician for decisions about your health.