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Peptide reconstitution calculator, made simple
Your peptide comes as a dry powder in a small glass bottle. You mix it with water, then use a syringe to measure it out. Answer 4 quick questions and we'll tell you exactly where to fill your syringe to. No math needed.
1 Question 1 of 4
Look at the label on the bottle. Find the number with mg after it, like "10 mg". That's how much powder is inside.
Don't see your number? Type any amount in the box.
2 Question 2 of 4
This is the water you mix into the powder. It's called bacteriostatic water. We've filled in 3 mL. Change it if you're adding a different amount. More water just makes a weaker mix, so you fill the syringe higher.
Don't see your number? Type any amount in the box.
3 Question 3 of 4
This number comes from your own plan. We never pick it for you. It's set to mg. If your number is in mcg, tap the mcg button. (1 mg is the same as 1,000 mcg.)
Type any amount, including decimals like 0.25.
4 Question 4 of 4
Which syringe are you using?
Look at the numbers printed on your syringe. Insulin syringes count in lines and go up to 30, 50 or 100. Regular syringes are marked in mL, like "3 mL". We've picked the 100-line insulin syringe. Tap yours if it's different.
Insulin syringes (marked in lines)
Regular syringes (marked in mL)
Your answer
Fill your syringe to the
—line
Plus a little left over in the vial.
Words you'll see
- Vial
- The small glass bottle with a rubber top. Your peptide powder is inside.
- Reconstitute
- A fancy word for "mix the powder with water."
- Bacteriostatic water
- Clean, sterile water with a tiny bit of preservative so germs don't grow in it. This is the water you mix in.
- mg
- Milligram. A tiny amount of weight. Vial labels use it.
- mcg
- Microgram. Even tinier. 1,000 mcg = 1 mg.
- mL
- Milliliter. A small amount of liquid. A teaspoon is about 5 mL.
- Insulin syringe
- A small syringe with lines numbered up to 30, 50 or 100.
- Units
- The lines on an insulin syringe. 100 units = 1 mL. When we say "fill to the 10 line," that's 10 units.
- Regular syringe
- A syringe marked in mL instead of lines, like 1, 3, 5 or 10 mL.
What you need
- Your vial of peptide powder
- Bacteriostatic water
- Syringes (insulin syringes with lines, or regular ones marked in mL)
- Alcohol wipes
How to mix the vial, step by step
- Wash your hands.Clean hands and a clean table.
- Wipe both rubber tops.Use an alcohol wipe on the top of the powder vial and the top of the water bottle. Let them dry.
- Pull up the water.Push the needle through the water bottle's rubber top and pull back the plunger to the amount you picked in question 2. A 100-line insulin syringe only holds 1 mL, so for 3 mL you do this 3 times, or use a bigger regular syringe for the water.
- Add the water slowly.Push the needle into the powder vial. Point it at the glass wall and push the water in slowly, so it runs down the side. Don't spray it straight onto the powder.
- Swirl, don't shake.Gently roll or swirl the vial until all the powder is gone. Shaking can damage the peptide. If it's slow, let it sit a few minutes.
- Check it.The liquid should look clear. If it looks cloudy or has bits floating in it, don't use it.
- Label it and keep it cold.Write the date on the vial and store it in the fridge (not the freezer).
How to read the syringe
- Insulin syringe: the big numbers (10, 20, 30…) are printed every 10 lines. On a 100-line syringe each small mark between them is 2 lines. On the 30- and 50-line syringes each small mark is 1 line.
- Regular syringe: the numbers are mL. The small marks split each mL into smaller steps, like 0.1 or 0.2 mL.
- Line up the top flat edge of the black rubber inside the syringe with your mark. That edge is what you read, not the pointy tip.
- Answer not exactly on a mark? Fill to the closest mark you can see.
An example
You have a 15 mg vial. You add 3 mL of water. You want 0.25 mg each time. You use a 100-line insulin syringe.
Answer: fill your syringe to the 5 line. That vial gives you 60 fills.
Why? 15 mg in 3 mL means every 1 mL holds 5 mg. 0.25 mg is 1/20th of that, and 1/20th of 100 lines is 5 lines.
Simple questions
Does more water mean less peptide?
No. The vial has the same amount of peptide no matter how much water you add. More water just spreads it out, so you fill the syringe higher to get the same amount.
I already added a different amount of water. Is that a problem?
No. Type the amount you really added into question 2. The answer changes to match.
Why does it say "lines" or "units" and not mL?
Because insulin syringes are marked in lines, not mL. 100 lines = 1 mL, so 10 lines is 0.1 mL. If you pick a regular syringe in question 4, the answer is in mL instead.
Does the answer change on a 30- or 50-line insulin syringe?
No. The lines mean the same thing on every insulin syringe. A smaller one just runs out of room sooner. If your answer is bigger than your syringe goes, the calculator tells you.
Who decides how much I want each time?
You do. This calculator only does the math on the numbers you type. It never picks an amount for you.
I want to work backwards, like "how much water do I need?"
Use the advanced reconstitution calculator. It can solve for any number you leave blank.