ReconstlyReconstitution Assistant
Peptide Reconstitution Calculator
Simple, visual reconstitution calculations.
How reconstitution calculations work
A peptide reconstitution calculator turns the numbers on your vial, the water added and the amount you want to measure into a volume and a syringe reading. Reconstly performs calculations from values you enter — it doesn’t know what is in your vial and doesn’t recommend amounts.
Reconstitution means adding a liquid, such as bacteriostatic water or sterile water, to the powder in a vial. Which liquid is appropriate depends on the product, so follow its instructions and professional guidance. The arithmetic is the same whichever liquid is used.
- Concentration = amount in the vial ÷ water added
- Volume to draw = amount to measure ÷ concentration
- Syringe units = volume in mL × 100 on a U-100 syringe, where 1 mL = 100 units
Keep units consistent: 1 mg = 1000 mcg. Mixing up mg and mcg changes the answer by a factor of 1000.
Example calculation
Example numbers only, to show the arithmetic:
- 10 mg ÷ 2 mL = 5 mg/mL
- 500 mcg = 0.5 mg
- 0.5 mg ÷ 5 mg/mL = 0.10 mL
- 0.10 mL × 100 = 10 units on a U-100 syringe
This is an arithmetic example, not a suggested amount.
How does water volume change the syringe measurement?
The amount in the vial stays the same, so adding more water spreads it through a larger volume. The same amount then fills more of the syringe. For a 10 mg vial and 500 mcg to measure:
| Water added | Concentration | Volume | U-100 units |
|---|---|---|---|
| 1 mL | 10 mg/mL | 0.05 mL | 5 units |
| 2 mL | 5 mg/mL | 0.10 mL | 10 units |
| 3 mL | ≈ 3.33 mg/mL | 0.15 mL | 15 units |
The comparison doesn’t rank these options — they are different ways of measuring the same amount. Choose “How much water do I add?” above to see this comparison for your own values.
What does U-100 mean?
U-100 describes a syringe scale where 100 units equal 1 mL. It is the scale commonly printed on insulin syringes.
- 100 units = 1.00 mL
- 50 units = 0.50 mL
- 10 units = 0.10 mL
- 5 units = 0.05 mL
Reconstly models U-100 syringes of 0.3 mL, 0.5 mL and 1 mL with the markings listed in the calculator. Not all syringes are U-100 — check the markings on yours.
Frequently asked questions
What is a peptide reconstitution calculator?
It works out the concentration after water is added to a vial (the amount in the vial divided by the water volume), then the volume and U-100 syringe units that match an amount you enter. Reconstly also shows where that measurement sits on the syringe you choose.
How do I calculate how many syringe units to draw?
Divide the amount you want to measure by the concentration to get millilitres, then multiply by 100 for a U-100 syringe. For example, 0.5 mg at 5 mg/mL is 0.10 mL, which is 10 units. Convert both amounts to the same unit (mg or mcg) first.
How many units is 0.1 mL on a U-100 syringe?
10 units. On a U-100 syringe 1 mL is 100 units, so 0.1 mL × 100 = 10 units.
How does the amount of water change the syringe measurement?
More water lowers the concentration, so the same amount takes up more volume and more units. With 10 mg in the vial and 500 mcg to measure, 1 mL of water gives 5 units, 2 mL gives 10 units and 3 mL gives 15 units.
Can Reconstly calculate how much water to add?
Yes, as arithmetic. The “How much water do I add?” option compares water volumes and shows how each one would measure on your syringe. You can also enter a position on the syringe and Reconstly works out the matching water volume. It does not tell you which option to choose.
What is the difference between mg and mcg?
Both measure mass. 1 milligram (mg) = 1000 micrograms (mcg), so 500 mcg = 0.5 mg. Reconstly shows mg and mcg in different colours and converts between them exactly.
What does U-100 mean?
It describes the syringe scale: 100 units equal 1 mL, so each unit is 0.01 mL. Not all syringes are U-100.
Does Reconstly recommend peptide doses?
No. Reconstly performs calculations from values you enter. It does not recommend doses, concentrations, water volumes or products, and it cannot check whether a value is appropriate for you. Follow the product’s instructions and qualified professional guidance, and confirm your values and equipment before use.