Tirzepatide
GLP-1 / GIP dual agonistVials: 5, 10, 15, 20, 30, 40, 50, 60, 120 mg · dose in mg
Peptide calculator
Enter the vial size, the bacteriostatic water you add and your dose. The calculator shows how many units to draw on an insulin syringe, the volume in mL and how many doses the vial holds.
Dose unit
Syringe scale
1Vial size
mg
2Bacteriostatic water added
mL
3Dose per injection
mg
4Syringe (U-100)
Draw to
units
= 0.5 mL on a 1 mL U-100 insulin syringe10 mg vial2 mL water2.5 mg dose
- Concentration
- 5 mg/mL
- Doses per vial
- 4
- Weeks (1 dose/wk)
- 4
50 units (0.5 mL) on a 1 mL U-100 syringe: 2.5 mg from a 10 mg vial + 2 mL water.
Dosing table for a 10 mg vial
Syringe units (U-100) for each dose, by how much bacteriostatic water you add.
| Dose | 1 mL water | 2 mL water | 2.5 mL water | 3 mL water |
|---|---|---|---|---|
| 0.25 mg | 2.5 | 5 | 6.25 | 7.5 |
| 0.5 mg | 5 | 10 | 12.5 | 15 |
| 1 mg | 10 | 20 | 25 | 30 |
| 2 mg | 20 | 40 | 50 | 60 |
| 2.5 mg | 25 | 50 | 62.5 | 75 |
| 5 mg | 50 | 100 | 125 | 150 |
| 7.5 mg | 75 | 150 | 187.5 | 225 |
| 10 mg | 100 | 200 | 250 | 300 |
How the math works
Concentration is the vial's milligrams divided by the water you add. Volume to draw is your dose divided by that concentration. On a U-100 syringe, 1 mL is 100 units, so units = mL × 100.
10 mg ÷ 2 mL = 5 mg/mL2.5 mg ÷ 5 mg/mL = 0.5 mL0.5 mL × 100 = 50 units
50 units · 0.5 mL · 2.5 mg from 10 mg + 2 mL
By peptide
Calculators for each peptide
Vial sizes are preset for each peptide, and the dose unit (mg or mcg) matches how the peptide is usually discussed.
GLP-1 & metabolic
FDA approved (Mounjaro, Zepbound)
Retatrutide
GLP-1 / GIP / glucagon triple agonistVials: 5, 10, 12, 15, 20, 24, 30, 36, 40, 50, 60 mg · dose in mg
Semaglutide
GLP-1 agonistVials: 2, 3, 5, 10, 15, 20, 30 mg · dose in mg
MOTS-c
Mitochondrial-derived peptideVials: 5, 10, 20, 40 mg · dose in mg
AOD-9604
HGH fragment analogVials: 2, 5, 10 mg · dose in mcg
5-Amino-1MQ
NNMT inhibitor (not a peptide)Vials: 5, 10 mg · dose in mg
Cagrilintide
Amylin analogVials: 2.5, 5, 10 mg · dose in mg
SLU-PP-332
ERR agonist (not a peptide)Vials: 5 mg · dose in mg
Healing & recovery
TB-500
Synthetic fragment of thymosin beta-4Vials: 2, 5, 10, 20 mg · dose in mg
BPC-157
Gastric pentadecapeptideVials: 2, 5, 10, 20 mg · dose in mcg
KPV
Anti-inflammatory tripeptideVials: 5, 10, 20 mg · dose in mcg
Growth hormone
Tesamorelin
GHRH analogVials: 2, 5, 10, 20 mg · dose in mg
Sermorelin
GHRH analogVials: 2, 5, 9, 15 mg · dose in mcg
IGF-1 LR3
IGF-1 analogVials: 0.1, 1 mg · dose in mcg
Ipamorelin
GHRP (ghrelin receptor agonist)Vials: 2, 5, 10 mg · dose in mcg
CJC-1295
GHRH analogVials: 2, 5, 10 mg · dose in mcg
Cognitive & sleep
Skin & hair
GHK-Cu
Copper tripeptideVials: 50, 100, 200 mg · dose in mg
Longevity
Sexual & hormonal health
PT-141
Melanocortin agonistVials: 10 mg · dose in mg
Melanotan II
Melanocortin agonistVials: 10 mg · dose in mcg
Kisspeptin-10
GnRH stimulatorVials: 5, 10 mg · dose in mcg
Other
Oxytocin
Neuropeptide hormoneVials: 2, 10 mg · dose in mcg
Blends
KLOW blend calculatorGHK-Cu + BPC-157 + TB-500 + KPVGLOW blend calculatorGHK-Cu + BPC-157 + TB-500Wolverine blend calculatorBPC-157 + TB-500CJC-1295 + Ipamorelin blend calculatorCJC-1295 (no DAC) + IpamorelinTesamorelin + Ipamorelin blend calculatorTesamorelin + IpamorelinSermorelin + Ipamorelin blend calculatorSermorelin + Ipamorelin
Method
How to use the calculator
A worked example: a 10 mg vial, 2 mL of bacteriostatic water and a 2.5 mg dose on a 1 mL U-100 syringe.
01
Read the vial
The label gives the total amount in mg, here 10 mg. Reconstituting does not change it.
02
Find the concentration
Divide the mg by the water you add: 10 mg ÷ 2 mL = 5 mg/mL.
03
Find the volume
Divide the dose by the concentration: 2.5 mg ÷ 5 mg/mL = 0.50 mL.
04
Convert to units
On a U-100 syringe 1 mL is 100 units: 0.50 mL × 100 = 50 units. The vial holds 4 such doses.
Syringes
How to read an insulin syringe
Insulin syringes are marked in units, not mL. The scale printed on the barrel tells you how many units make 1 mL.
0.3 mL U-100 syringe
Holds 30 units. Each unit is 0.01 mL, so 10 units is 0.1 mL.
0.5 mL U-100 syringe
Holds 50 units. Each unit is 0.01 mL, so 10 units is 0.1 mL.
1 mL U-100 syringe
Holds 100 units. Each unit is 0.01 mL, so 10 units is 0.1 mL.
U-40 syringes
A 1 mL U-40 syringe holds 40 units, so each unit is 0.025 mL and 10 units is 0.25 mL. A units number from a U-100 chart drawn on a U-40 syringe gives 2.5 times the volume.
Converters
Quick conversions
Common questions
How many units is 2.5 mg?
It depends on the concentration. In a 10 mg vial mixed with 2 mL of water (5 mg/mL), 2.5 mg is 50 units (0.50 mL) on a U-100 syringe. With 1 mL of water it is 25 units; with 3 mL it is 75 units.
How much bacteriostatic water do I add to a 10 mg vial?
Any volume works mathematically; the water only sets the concentration. 1 mL gives 10 mg/mL, so 1 mg is 10 units; 2 mL gives 5 mg/mL, so 1 mg is 20 units; 3 mL gives 3.33 mg/mL, so 1 mg is 30 units. More water makes small doses easier to measure but means more volume per injection.
How many units is 250 mcg?
250 mcg is 0.25 mg. From a 5 mg vial with 2 mL of water it is 10 units (0.10 mL) on a U-100 syringe; from a 10 mg vial with 2 mL it is 5 units.
How many mL is 10 units on an insulin syringe?
On a U-100 syringe 10 units is 0.1 mL. On a U-40 syringe the same 10 units is 0.25 mL.
What is the difference between U-100 and U-40 syringes?
A U-100 syringe has 100 unit marks per mL; a U-40 syringe has 40. The same 0.25 mL reads 25 units on U-100 and 10 units on U-40. Reading a units number on the wrong scale changes the volume by 2.5 times, so always use the scale printed on your syringe.
How many doses are in a vial?
Divide the vial's milligrams by the dose: 10 mg ÷ 2.5 mg = 4 doses. The water you add does not change the number of doses, only the volume of each one.
Sources
- 1Metric (SI) Prefixes (NIST Reference on Constants, Units, and Uncertainty)National Institute of Standards and Technology (NIST) · 2025physics.nist.govAccessed 2 Oct 2026
- 2BASAGLAR (insulin glargine) injection, prescribing information (DailyMed)U.S. Food and Drug Administration / DailyMed (Eli Lilly and Company label) · 2026dailymed.nlm.nih.govAccessed 2 Oct 2026
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