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Peptide Dosage
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Reconstitution Calculator

?This calculator figures out how much liquid to draw into your syringe based on how much peptide is in your vial and how much water you added. Just fill in the boxes below!

Fill in your vial details — we'll do the math for you.

Popular Peptides (tap to auto-fill)?If you're using one of these common peptides, tap it to pre-fill the typical vial size, water amount, and starting dose. You can still adjust everything afterwards.
mg
mL
mg
That's 250 mcg
units
Your Results ?These are your calculated results. The two most important numbers are "Draw to" (how many units to pull on your syringe) and "Volume" (how many mL that is). They mean the same thing, just measured differently!
Concentration?How much peptide is in each mL of liquid after mixing. Higher concentration = less liquid per dose.
2.50mg/mL
Draw To?This is the line you pull back to on your syringe. Line up the black rubber stopper with this number on your syringe barrel.
10.0IU
Volume?The same measurement as "Draw to" but in milliliters instead of syringe units. Some people find mL easier to understand.
0.100mL
Doses / Vial?How many times you can dose from this single vial before it runs out at your current dose amount.
20
Your syringe fill level?This shows what your syringe would look like filled to the correct dose. The green liquid level rises to match your dose. The arrow shows exactly where to stop drawing.
Draw to 10 IU
This vial will give you 20 doses at this amount
In Plain English

Add 2 mL of bacteriostatic water to your 5 mg vial. To get a 0.25 mg (250 mcg) dose, draw your syringe to the 10 unit mark. You'll get about 20 doses from this vial.

How to Reconstitute Peptides: Step-by-Step?A step-by-step beginner's guide to reconstituting (mixing) your peptide vial. This is the process of adding water to the powder so you can inject it.

A simple, beginner-friendly guide to mixing your peptide vial

1

Gather Your Supplies

You'll need: your lyophilized (freeze-dried) peptide vial, a vial of bacteriostatic water (BAC water), an insulin syringe (usually 1mL / 100 units), and alcohol prep pads. Wash your hands thoroughly before starting.

2

Determine Your Water Volume

Use the calculator above to decide how much BAC water to add. A popular choice is 2 mL per 5 mg vial — this creates easy-to-measure doses. The amount of water doesn't change the total peptide — it only changes the concentration.

3

Wipe Both Vials & Add Water Slowly

Swab the rubber stoppers on both vials with alcohol pads. Draw your calculated amount of BAC water into the syringe. Insert into the peptide vial and let the water drip slowly down the inside glass wall — never squirt directly onto the lyophilized powder.

4

Swirl Gently — Never Shake

Roll the vial between your palms or swirl very gently. Vigorous shaking can damage peptide bonds and reduce potency. Wait until the powder is completely dissolved — the solution should be perfectly clear with no visible particles.

5

Draw Your Dose & Refrigerate

Using a fresh insulin syringe, draw to the unit mark shown in the calculator results above. Store the reconstituted vial upright in your refrigerator (36-46°F / 2-8°C). Most peptides remain stable for 4-6 weeks when properly refrigerated.

Reconstitution Supplies Checklist

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Insulin Syringes

29-31 gauge, 1mL (100 units) or 0.5mL

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Alcohol Prep Pads

Sterile, individually wrapped, 70% isopropyl

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Vial Storage Case

Insulated travel case, fridge-ready

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Sharps Container

Safe at-home disposal for used insulin syringes

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Peptide Protocol Cost Calculator

?Want to know how much your peptide protocol costs per week or month? This uses the dosing info above plus your vial price to figure it out.

Find out what your peptide protocol actually costs per dose, week, and month.

$
x / week
Per Dose
$2.00
Per Week
$14.00
Per Month
$60.67

Peptide Dosage Reference Chart?This table shows typical dosing ranges for popular peptides. These are general guidelines only. Always follow your provider's instructions.

Standard reconstitution and dosage ranges for the most common peptides

PeptideTypical Vial SizeCommon Dose RangeDosing FrequencyBAC Water
Retatrutide5 - 12 mg0.5 - 12 mg1x weekly2 - 3 mL
Semaglutide2 - 5 mg0.25 - 2.4 mg1x weekly1 - 2 mL
Tirzepatide5 - 15 mg2.5 - 15 mg1x weekly2 - 3 mL
BPC-1575 mg250 - 500 mcg1-2x daily2 mL
TB-5005 mg2 - 5 mg2x weekly2 mL
CJC-1295 / Ipamorelin2 - 5 mg100 - 300 mcg1-3x daily2 mL
GHK-Cu5 mg200 - 500 mcg1x daily2 mL
PT-14110 mg1 - 2 mgAs needed2 mL
AOD-96045 mg250 - 500 mcg1x daily2 mL
GHRP-65 mg100 - 300 mcg1-3x daily2 mL
MOTS-c5 - 10 mg5 - 10 mg1-3x weekly2 mL

Peptide Reconstitution FAQ?Answers to the most common questions beginners have about peptide reconstitution, dosing, and storage.

What do the "units" on my insulin syringe mean?+
The numbers on an insulin syringe measure volume, not medication strength. A standard 1mL syringe goes up to 100 units. So 10 units = 0.1mL, and 50 units = 0.5mL. Think of "units" as just tiny mL markings. Our peptide calculator tells you exactly which unit number to draw to.
Does it matter how much bacteriostatic water I use?+
Not really — the total peptide stays the same regardless of how much water you add. More water just means each mL has less peptide, so you'd draw more liquid per dose. Less water means smaller injections but harder to measure precisely. Most people use 1-3 mL. The peptide reconstitution calculator adjusts automatically.
What's bacteriostatic water and why can't I use regular water?+
Bacteriostatic water (BAC water) is sterile water with 0.9% benzyl alcohol added to prevent bacterial growth. This is important because you'll draw from the same vial multiple times over several weeks. Regular tap or bottled water would allow bacteria to grow. Sterile water (without benzyl alcohol) is only safe for single-use applications. BAC water is available online and at most pharmacies.
How long do reconstituted peptides last in the fridge?+
When stored properly in a refrigerator at 36-46°F (2-8°C), most reconstituted peptides remain potent for 4-6 weeks. Keep the vial upright, avoid leaving it at room temperature, and always swab the stopper with an alcohol pad before each use. If the solution looks cloudy, discolored, or has visible particles, discard it immediately.
What's the difference between mcg and mg?+
They're both measurements of weight. 1 mg (milligram) = 1,000 mcg (micrograms). So 250 mcg is the same as 0.25 mg. Peptide doses are often written in mcg because the amounts are so small. Our calculator displays both units so there's no confusion about your dosage.
Should I use a different syringe to reconstitute vs. inject?+
Ideally yes. The needle tip gets slightly dulled each time it punctures a rubber vial stopper, making injections less comfortable. Best practice is to use one syringe to add the BAC water, then a fresh syringe each time you draw a dose for injection. Insulin syringes are inexpensive enough to use one per injection.
How do I calculate peptide concentration after reconstitution?+
Divide the total peptide amount (in mg) by the amount of water added (in mL). For example: 5 mg peptide + 2 mL BAC water = 2.5 mg/mL concentration. This means every 0.1 mL (10 units on a syringe) contains 0.25 mg (250 mcg). The calculator above does this math for you automatically.

Free Peptide Reconstitution Cheat Sheet

A printable, fridge-friendly reference card with dosing charts for the 10 most common peptides. No math required — just look up your peptide and go.

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