Is this a peptide dosage calculator?

No. It runs reconstitution and syringe-unit math for laboratory research: the concentration (mg/mL) of a mixed vial and the equivalent units on a U-100 syringe scale. It does not recommend how much of any compound to use, for a person or an animal. If you searched 'dosage calculator,' the reconstitution math above is almost certainly what you need: turning a vial size and a water volume into a concentration and a syringe mark.

How much bacteriostatic water do I add to a peptide vial?

There is no single fixed amount: the volume you add sets the concentration, so pick a volume that makes your draw easy to measure. Common choices: 2 mL into a 5 mg vial gives 2.5 mg/mL, and 2 mL into a 10 mg vial gives 5 mg/mL. More water means a lower concentration and more units per draw (easier to measure but a fuller syringe); less water means a higher concentration and fewer units. Use the calculator above to test any combination.

How do I read units on a U-100 syringe scale for peptides?

A standard U-100 syringe scale is marked in units where 100 units = 1 mL, so 1 unit = 0.01 mL. To find your draw, multiply your volume per draw in mL by 100. For example, 0.05 mL = 5 units, and 0.10 mL = 10 units. The 'units' and 'IU' markings on the barrel refer to the same lines; 1 cc = 1 mL exactly.

How long does reconstituted peptide last, and how should it be stored?

Once mixed with bacteriostatic water, most peptides are stable for about 28 days when refrigerated at 2-8°C (36-46°F) and kept out of light. The 0.9% benzyl alcohol in BAC water acts as a preservative. Do not freeze a reconstituted vial, and discard it if the solution turns cloudy or discolored. Lyophilized (un-mixed) peptide powder keeps far longer: months to years frozen at -20°C. Check the supplier's sheet for the specific compound.

Can I reuse the same peptide vial for multiple draws?

Yes, that is the point of bacteriostatic water. The benzyl alcohol preservative makes the vial multi-use, so you can take repeated draws over roughly 28 days refrigerated. Wipe the rubber stopper with a fresh alcohol swab before every draw, use a new sterile needle each time, and never return drawn solution to the vial. If you reconstitute with plain sterile water instead, the vial has no preservative and should be treated as single-use within 24 hours.

What syringe is best for small peptide draws?

For most research draws, a U-100 (1 mL) syringe is marked directly in units (100 units = 1 mL), so the units you calculate read straight off the barrel scale, with no mL conversion. For very small draws (under 5 units), a 0.3 mL (30-unit) syringe has more widely spaced markings, so the line is easier to read. If a single draw would exceed 100 units, reconstitute with less water to raise the concentration so it fits on one barrel, or split it into smaller draws.

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Peptide Calculator

Q: What is the peptide reconstitution formula?

Concentration (mg/mL) = mg of peptide ÷ mL of bacteriostatic water. Then the units to draw on a U-100 syringe scale = (target amount in mg ÷ concentration in mg per mL) × 100. Example: 10 mg of peptide in 2 mL of BAC water is 5 mg/mL; a 250 mcg (0.25 mg) target is 0.25 ÷ 5 = 0.05 mL = 5 units.

Reconstitution and syringe-unit math. Research use only.

Start from a preset

All 34 presets

Peptide in Vial

Total peptide mass on the vial label

BAC Water Added

Amount of bacteriostatic water to add

Target Amount

Target amount per draw (research reference)

Add vial price to see cost per draw

Vial Price (optional)

What you paid for the vial, used to compute cost per draw

Draw to

10.0

units

for a 500 mcg amount. That is 0.100 mL per draw.

U-100 syringe

100

10.0 units

Draw to this line

What next

Compare peptide pricesPrice per mg across vendors Get the cheat sheetFree PDF, 38 compounds and blends Intranasal calculatormcg per spray and sprays per bottle Reconstitution guideFive mixing steps, plus storage

Concentration

5.00

mg/mL

5000 mcg/mL

Volume per Draw

0.100

Volume to draw from the vial

Syringe Draw

10.0

units

On a U-100 syringe scale

Draws per Vial

draws

Research use only. This tool performs reconstitution math: concentration and syringe-unit conversion. It is not dosing guidance for humans or animals.

Example: 10 mg vial + 2 mL BAC water = 5 mg/mL. At that concentration, a 250 mcg amount = 0.05 mL = 5 units on a U-100 syringe scale.

Quick Syringe Reference

Units

Volume (mL)

Amount (mcg)

Amount (mg)

0.05

250

0.250

10you

0.10

500

0.500

0.15

750

0.750

0.20

1000

1.000

0.25

1250

1.250

0.50

2500

2.500

How peptide reconstitution works

Peptide reconstitution means dissolving a freeze-dried (lyophilized) peptide powder in bacteriostatic water so it can be drawn up into a syringe and measured. Two numbers decide your draw: the concentration of the mixed vial, and your target amount. The answer is a number of units on a U-100 syringe scale.

The peptide reconstitution formula

concentration (mg/mL) = mg of peptide / mL of BAC water

units on a U-100 syringe scale = (target amount in mg / concentration in mg per mL) × 100

On a U-100 syringe, 100 units = 1 mL, so 1 unit = 0.01 mL. To convert an amount in micrograms to milligrams, divide by 1,000 (250 mcg = 0.25 mg).

In one sentence: divide the peptide mass by the water volume to get concentration, divide your target amount by that concentration to get the volume in mL, then multiply by 100 to get syringe units.

Worked examples

Example 1: BPC-157, 10 mg vial

10 mg peptide + 2 mL BAC water = 5 mg/mL. For a 250 mcg (0.25 mg) amount: 0.25 / 5 = 0.05 mL = 5 units on a U-100 syringe.

Example 2: Semaglutide, 5 mg vial

5 mg peptide + 2 mL BAC water = 2.5 mg/mL. For a 250 mcg (0.25 mg) amount: 0.25 / 2.5 = 0.10 mL = 10 units on a U-100 syringe.

Example 3: Tirzepatide, 60 mg vial

60 mg peptide + 6 mL BAC water = 10 mg/mL. For a 2.5 mg amount: 2.5 / 10 = 0.25 mL = 25 units on a U-100 syringe.

Add the water slowly down the inside wall of the vial. Never spray it directly onto the powder. Swirl gently to dissolve; do not shake. Store the reconstituted vial refrigerated at 2-8°C (36-46°F) and use it within about 28 days. Bacteriostatic water contains 0.9% benzyl alcohol, a preservative that lets a multi-use vial stay usable for roughly four weeks refrigerated; plain sterile water has no preservative and should be used within 24 hours.

Sourcing note: some peptide vendors sell bacteriostatic water alongside their vials. Check the label for 0.9% benzyl alcohol.

Reconstitution reference

Five mixing steps, the mg/mL math with a worked example, and storage.

Read the reconstitution guide

All 34 presets

Click Load on any row to auto-fill the calculator above.

Healing & Recovery

Peptide	Vial	Solvent	Amount	Syringe
BPC-157	10 mg	2 mL BAC	500 mcg	10.0 units
TB-500	10 mg	2 mL BAC	3000 mcg	60.0 units
BPC/TB Blend	20 mg	2 mL BAC	500 mcg	5.0 units
GHK-Cu	50 mg	3 mL BAC	2000 mcg	12.0 units
KPV	10 mg	2 mL BAC	500 mcg	10.0 units
Thymosin α1	10 mg	2 mL BAC	1500 mcg	30.0 units
Glow Blend	70 mg	3 mL BAC	1670 mcg	7.2 units
KLOW Blend	80 mg	3 mL BAC	1670 mcg	6.3 units

Fat Loss & Metabolic

Peptide	Vial	Solvent	Amount	Syringe
Semaglutide	30 mg	3 mL BAC	500 mcg	5.0 units
Tirzepatide	60 mg	6 mL BAC	2500 mcg	25.0 units
Retatrutide	10 mg	3 mL BAC	1000 mcg	30.0 units
Cagrilintide	10 mg	2 mL BAC	250 mcg	5.0 units
Tesamorelin	10 mg	2 mL BAC	1000 mcg	20.0 units
MOTS-c	10 mg	2 mL BAC	1000 mcg	20.0 units
5-Amino-1MQ	10 mg	2 mL BAC	1000 mcg	20.0 units
AOD-9604	5 mg	2 mL BAC	300 mcg	12.0 units

Growth Hormone

Peptide	Vial	Solvent	Amount	Syringe
CJC/Ipa Blend	10 mg	2 mL BAC	250 mcg	5.0 units
Ipamorelin	5 mg	2 mL BAC	250 mcg	10.0 units
Sermorelin	5 mg	2 mL BAC	250 mcg	10.0 units
GHRP-2	5 mg	2 mL BAC	200 mcg	8.0 units
GHRP-6	5 mg	2 mL BAC	200 mcg	8.0 units
Hexarelin	2 mg	2 mL BAC	150 mcg	15.0 units
IGF-1 LR3acetic acid	1 mg	1 mL (acetic acid)	100 mcg	10.0 units
HGH Frag 176-191	5 mg	2 mL BAC	350 mcg	14.0 units

Cognitive & Mood

Peptide	Vial	Solvent	Amount	Syringe
Semax	30 mg	3 mL BAC	1000 mcg	10.0 units
Selank	30 mg	3 mL BAC	1000 mcg	10.0 units
Oxytocin	5 mg	2 mL BAC	50 mcg	2.0 units
DSIP	5 mg	2 mL BAC	200 mcg	8.0 units
Kisspeptin-10	5 mg	2 mL BAC	75 mcg	3.0 units

Immune & Longevity

Peptide	Vial	Solvent	Amount	Syringe
NAD+	500 mg	5 mL BAC	75000 mcg	75.0 units
Epithalon	10 mg	2 mL BAC	7500 mcg	150.0 units
LL-37	5 mg	2 mL BAC	175 mcg	7.0 units

Sexual & Cosmetic

Peptide	Vial	Solvent	Amount	Syringe
PT-141	10 mg	2 mL BAC	500 mcg	10.0 units
Melanotan 2	10 mg	2 mL BAC	250 mcg	5.0 units

Frequently Asked Questions

Embed This Calculator on Your Site

Drop the reconstitution calculator into any blog post, documentation page, or vendor product page. Free, with optional white-label mode. Pre-fill values via ?vial=5&water=2&dose=250 or add cost-per-draw math with ?price=85. Match your brand with ?accent=%23hex and ?vendor=Your%20Brand.

<iframe src="https://www.bodyhackguide.co/embed/reconstitution" width="100%" height="640" frameborder="0" loading="lazy" title="Peptide Reconstitution Calculator" style="border:0;border-radius:14px;max-width:780px"></iframe>

Preview the embed·See the 5 drop-in presets and the URL parameter docs

Compound-Specific Calculators

Pre-filled reconstitution calculators for popular peptides. Tap to jump straight to your compound.

BPC-1575 mg vial · 250 mcg TB-5005 mg vial · 2500 mcg Semaglutide5 mg vial · 250 mcg Tirzepatide10 mg vial · 2500 mcg Retatrutide10 mg vial · 2000 mcg CJC-1295 (Mod GRF 1-29)2 mg vial · 100 mcg Ipamorelin5 mg vial · 200 mcg GHK-Cu5 mg vial · 200 mcg PT-141 (Bremelanotide)10 mg vial · 1750 mcg Semax5 mg vial · 200 mcg Selank5 mg vial · 250 mcg MOTS-c5 mg vial · 5000 mcg AOD-96045 mg vial · 300 mcg DSIP2 mg vial · 100 mcg Epithalon10 mg vial · 5000 mcg

Free 2026 Peptide Cheat Sheet (PDF)

38 compounds and blends: vial sizes, BAC water volumes, dosing ranges and bloodwork markers.

Download Free

Research Use Only

Peptide Calculator

What next

Quick Syringe Reference

How peptide reconstitution works

Reconstitution reference

All 34 presets

Healing & Recovery

Fat Loss & Metabolic

Growth Hormone

Cognitive & Mood

Immune & Longevity

Sexual & Cosmetic

Related Guides

Frequently Asked Questions

Embed This Calculator on Your Site

Compound-Specific Calculators