Is the peptide calculator free?

Yes. It's free, with no sign-up and nothing to download. It works on any phone, tablet or computer.

How do I convert mg to units?

Divide your dose by the strength of the mix to get mL, then multiply by 100. For example, 0.5 mg ÷ 5 mg/mL = 0.1 mL, which is 10 units on a U-100 syringe. The calculator does this for you.

How many units is 1 mL?

On a U-100 insulin syringe, 1 mL is 100 units, so 2 mL is 200 units and 3 mL is 300 units. One unit is 0.01 mL.

Does more water give me more doses?

No. Water only changes the strength of the mix. The number of doses depends on the peptide in the vial and the size of each dose.

Why is my dose more than the syringe holds?

The mix is too weak for that dose, so it needs more liquid than the syringe takes. Use a bigger syringe, split it into two draws, or use less water when you mix the vial.

Does it work for blends?

Yes. Enter the total on the label, for example 10 mg for a 5 mg + 5 mg blend like CJC-1295 + Ipamorelin. Your dose is then for the whole mix, not one peptide in it.

Does it work as a retatrutide dosage calculator?

Yes. Choose Retatrutide 10mg, 20mg or 30mg in step 1, or type your vial size, then add your water and dose. The maths is the same for every peptide.

Does the calculator tell me what dose to use?

No. It only turns the dose you enter into units and mL. It never recommends an amount for any peptide. Our peptides are sold for laboratory research use only.

How accurate is the answer?

The maths is exact. Syringe lines are not, so round to the nearest line you can read. Under 2 units is hard to measure: use more water when you mix and the same dose fills more units.

Can I use a U-40 syringe?

Not with these results. The calculator gives U-100 units, where 100 units = 1 mL. A U-40 syringe has 40 units per mL, so its lines won't match.

Free reconstitution calculator

Peptide Calculator

Work out exactly how many units to draw. Pick your vial, add your water and dose, and the syringe shows the answer.

Peptide in the vial

Water you add

Your dose

Your answer

Enter your dose (step 3) to see the units

Your syringe

Strength: 5 mg/mL
Per unit: 50 mcg
Full doses: – doses

Using retatrutide? Pick Retatrutide 10mg, 20mg or 30mg in step 1 and this works as a retatrutide dosage calculator.

For laboratory research use only. The peptide calculator does the maths for the numbers you enter and never suggests a dose.

Step by step

How to use the peptide calculator

Four steps, the same whether you use it as a peptide calculator or a retatrutide dosage calculator. Every one has a ? beside it if you get stuck.

Enter the peptide in your vial
The amount of powder in your vial, printed on the label in mg. Pick one of our vials or type the number, for example 10.
Enter the water you add
How much bacteriostatic (bac) water you add to dissolve the powder. More water makes a weaker mix, so each dose takes more units.
Enter your dose
How much peptide you want in the syringe each time. Choose mcg or mg to match your number (1 mg = 1,000 mcg). The calculator never suggests a dose.
Pick your syringe
Check the pack: a 0.3 mL syringe holds 30 units, 0.5 mL holds 50 and 1 mL holds 100. All three are U-100, so 1 unit is always 0.01 mL.

Reading your answer

Units to draw: Pull the plunger back until the liquid reaches this line on your syringe. The mL figure is the same amount: 100 units is 1 mL.
Strength: How much peptide is in every mL of the vial once the powder and water are mixed.
Per unit: How much peptide each line (1 unit) on the syringe holds.
Full doses: How many full doses the vial gives at your dose. Adding more water doesn't change this.

The maths

Peptide calculator formula

Three simple sums turn your vial, water and dose into syringe units.

Strengthpeptide (mg) ÷ water (mL) = mg per mL
Volumedose (mg) ÷ strength = mL to draw
UnitsmL × 100 = units on a U-100 syringe

Worked example

10 mg vial, 2 mL of water, 500 mcg dose

Strength10 ÷ 2 = 5 mg/mL
Dose in mg500 mcg = 0.5 mg
Volume0.5 ÷ 5 = 0.1 mL
Units0.1 × 100 = 10 units
Full doses10 ÷ 0.5 = 20

Chart

Peptide reconstitution chart

The strength of common vial sizes with 1, 2 or 3 mL of bac water, worked out the same way as the calculator.

Top number: mg per mLBelow it: mcg in each unit

Peptide strength in mg per mL, and mcg per syringe unit, by vial size and water added
Vial	1 mL water	2 mL water	3 mL water
2 mg	2 mg/mL20 mcg	1 mg/mL10 mcg	0.67 mg/mL6.7 mcg
5 mg	5 mg/mL50 mcg	2.5 mg/mL25 mcg	1.67 mg/mL16.7 mcg
10 mg	10 mg/mL100 mcg	5 mg/mL50 mcg	3.33 mg/mL33.3 mcg
15 mg	15 mg/mL150 mcg	7.5 mg/mL75 mcg	5 mg/mL50 mcg
20 mg	20 mg/mL200 mcg	10 mg/mL100 mcg	6.67 mg/mL66.7 mcg
30 mg	30 mg/mL300 mcg	15 mg/mL150 mcg	10 mg/mL100 mcg

Bac water

How much bac water to add?

There's no single right amount. Most people add 1, 2 or 3 mL of bacteriostatic water.

More water

A weaker mix. Each dose takes more units, so small doses are easier to measure.

Less water

A stronger mix. Each dose takes fewer units, so bigger doses still fit in the syringe.

Water never changes how many doses you get. That comes from the vial size and your dose.
In syringe units, 1 mL of water is 100 units, 2 mL is 200 and 3 mL is 300.
Try a few amounts in the calculator first. Once the water is in the vial, it can't come out.

Syringes

Syringe units explained

Insulin syringes are marked in units. On a U-100 syringe, 100 units = 1 mL, so 1 unit = 0.01 mL.

U-100 insulin syringe sizes
Syringe	Holds	Lines usually every
0.3 mL	30 units	1 unit
0.5 mL	50 units	1 unit
1 mL	100 units	2 units

mg and mcg

1 mg = 1,000 mcg. Vials are labelled in mg and doses are often written in mcg, so pick the unit that matches your number in step 3.

U-40 syringes

These results are for U-100 syringes only. A U-40 syringe has 40 units per mL, so its lines don't match.

FAQ

Peptide calculator FAQs

Quick answers about using the calculator. Every answer is right here, nothing to open.

Is the peptide calculator free?: Yes. It's free, with no sign-up and nothing to download. It works on any phone, tablet or computer.
How do I convert mg to units?: Divide your dose by the strength of the mix to get mL, then multiply by 100. For example, 0.5 mg ÷ 5 mg/mL = 0.1 mL, which is 10 units on a U-100 syringe. The calculator does this for you.
How many units is 1 mL?: On a U-100 insulin syringe, 1 mL is 100 units, so 2 mL is 200 units and 3 mL is 300 units. One unit is 0.01 mL.
Does more water give me more doses?: No. Water only changes the strength of the mix. The number of doses depends on the peptide in the vial and the size of each dose.
Why is my dose more than the syringe holds?: The mix is too weak for that dose, so it needs more liquid than the syringe takes. Use a bigger syringe, split it into two draws, or use less water when you mix the vial.
Does it work for blends?: Yes. Enter the total on the label, for example 10 mg for a 5 mg + 5 mg blend like CJC-1295 + Ipamorelin. Your dose is then for the whole mix, not one peptide in it.
Does it work as a retatrutide dosage calculator?: Yes. Choose Retatrutide 10mg, 20mg or 30mg in step 1, or type your vial size, then add your water and dose. The maths is the same for every peptide.
Does the calculator tell me what dose to use?: No. It only turns the dose you enter into units and mL. It never recommends an amount for any peptide. Our peptides are sold for laboratory research use only.
How accurate is the answer?: The maths is exact. Syringe lines are not, so round to the nearest line you can read. Under 2 units is hard to measure: use more water when you mix and the same dose fills more units.
Can I use a U-40 syringe?: Not with these results. The calculator gives U-100 units, where 100 units = 1 mL. A U-40 syringe has 40 units per mL, so its lines won't match.