Peptide Concentration Calculator
Concentration is the number that makes every other calculation reproducible. Enter the vial mass and the diluent volume to see the resulting strength expressed three ways: milligrams per millilitre, micrograms per millilitre, and micrograms per single U-100 syringe unit.
- Concentration
- 5000 mcg / mL
- Concentration
- 5.00 mg / mL
- Per syringe unit
- 50.0 mcg / unit
- Draws per vial
- 20.0
- Total solution
- 200 units
Every figure below is arithmetic performed in your browser. Nothing here is a protocol, recommendation, or medical guidance — all Ares Research materials are supplied for in-vitro laboratory research only.
Three ways to express the same solution
A 10 mg vial in 2 mL is 5 mg/mL, 5,000 mcg/mL, and 50 mcg per unit — three descriptions of one solution. The mcg-per-unit figure is the most directly useful at the bench because it converts a syringe reading into a mass without further arithmetic: 12 units of a 50 mcg/unit solution is 600 mcg.
Label the vial with the concentration, not the vial strength
Once a vial is in solution, its nominal strength is no longer sufficient information. Two 10 mg vials reconstituted in 1 mL and 5 mL behave completely differently on a syringe. Write the mg/mL or mcg/unit figure on the vial at the moment of reconstitution; it is the only number that lets someone else reproduce your draw.
Working backwards from a target concentration
If you want a specific concentration — say exactly 10 mcg per unit — divide the vial mass in micrograms by the target mcg/mL. For 10 mcg per unit, the target is 1,000 mcg/mL, so a 10 mg (10,000 mcg) vial needs 10 mL of diluent. Adjust the water field above until the mcg-per-unit output reads the round number you want.
Frequently asked questions
How do I calculate peptide concentration?
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Divide the total peptide mass in the vial by the volume of diluent added. A 10 mg vial in 2 mL gives 5 mg/mL, or 5,000 mcg/mL. Divide that by 100 to get micrograms per U-100 syringe unit — in this case 50 mcg per unit.
How many mcg are in one unit on an insulin syringe?
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It depends entirely on the concentration. One unit is always 0.01 mL, so the mass it contains equals the concentration in mcg/mL divided by 100. At 5,000 mcg/mL, one unit holds 50 mcg; at 1,000 mcg/mL, one unit holds 10 mcg.
How much diluent do I need for a specific concentration?
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Divide the vial mass in micrograms by the target concentration in mcg/mL. For 1,000 mcg/mL from a 10,000 mcg (10 mg) vial, you need 10 mL. Adjust the diluent field above and read the resulting concentration to hit any round figure you want.
How should reconstituted material be stored?
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Once reconstituted, most research peptides are held refrigerated at roughly 2–8°C, protected from light, in the original sealed vial. Bacteriostatic water contains 0.9% benzyl alcohol, which suppresses microbial growth in the diluent. Temperature, light exposure, and repeated freeze-thaw cycles all affect stability, so consult the compound-specific certificate of analysis and published stability data.
How do I read a U-100 insulin syringe?
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A U-100 barrel is graduated in units where 100 units equal 1 mL, so each single-unit mark is 0.01 mL. To convert a volume in mL to units, multiply by 100 — 0.25 mL is 25 units. This calculator reports both figures so you can cross-check the mark against the volume.
Related calculators
Any vial, any diluent volume, any target amount → concentration, syringe units, doses per vial.
Compare diluent volumes before you mix — see how each one changes the syringe reading.
mL ↔ U-100 units, plus how many mcg each unit carries at your concentration.