Peptide Concentration Calculator
Concentration is the amount dissolved divided by the total liquid. Enter both to get mg/mL and mcg/mL, the amount in 0.1 mL and in one U-100 unit, and, if you want, the stock volume that makes a weaker solution.
Peptide Concentration Calculator
Concentration calculator
Enter the amount dissolved and the total liquid.
Arithmetic only: it never suggests or assesses an amount. Nothing you type leaves your browser.
The concentration formula
concentration (per mL) = amount dissolved ÷ total liquid (mL)Because 1 mg is 1,000 mcg, a concentration in mg/mL times 1,000 is the same concentration in mcg/mL. A 10 mg vial in 2 mL is 5 mg/mL, or 5,000 mcg/mL.
| Volume | U-100 units | Amount |
|---|---|---|
| 0.01 mL | 1 unit | 0.05 mg (50 mcg) |
| 0.05 mL | 5 units | 0.25 mg (250 mcg) |
| 0.1 mL | 10 units | 0.5 mg (500 mcg) |
| 1 mL | 100 units | 5 mg (5,000 mcg) |
Diluting a solution (C1 × V1 = C2 × V2)
To make a weaker solution from a stronger one, the amount stays the same: concentration times volume before equals concentration times volume after.
stock volume (V1) = weaker concentration (C2) × final volume (V2) ÷ stock concentration (C1)Example: from a 5 mg/mL stock, 3 mL at 1 mg/mL needs 1 × 3 ÷ 5 = 0.6 mL of stock, plus 2.4 mL of liquid. The calculator refuses a “weaker” concentration that is stronger than the stock.
Concentration in IU
For a product labelled in IU, choose IU: the concentration comes out in IU/mL. IU measures biological activity, so it converts to mg only with that product’s own IU-per-mg factor. The calculator never assumes one. See mg, mcg and IU explained.
Frequently asked questions
How do I work out mg/mL?
Divide the amount in mg by the volume in mL. 10 mg in 2 mL is 5 mg/mL.
How many mcg are in 1 mL?
It depends entirely on the concentration: at 2.5 mg/mL, 1 mL holds 2,500 mcg; at 5 mg/mL it holds 5,000 mcg. mL is a volume and mcg is a mass, so you can’t convert one to the other without a concentration.
Is 1000 mcg in 1 mL?
Only when the concentration is 1 mg/mL. 1,000 mcg is always 1 mg, but how much liquid holds it depends on the solution.
What does diluting a solution do?
It lowers the concentration while keeping the amount the same, so each amount takes up more volume. Use C1 × V1 = C2 × V2 to find how much stock to use.
Related calculators and guides
- CalculatorReconstitution calculatorWork out concentration after adding bacteriostatic water, then the mL and U-100 units for any amount.
- CalculatorMcg to mL calculatorConvert mcg to mL using your solution’s concentration, with U-100 syringe units and the nearest marking.
- GuideHow to Use a Peptide CalculatorA step-by-step guide to using a peptide calculator: the three numbers you need, how to read the result, and how to check the answer yourself in under a minute.
- CalculatorMg to mcg calculatorConvert mg to mcg and mcg to mg exactly (1 mg = 1,000 mcg), with a conversion table, and why IU converts only with a substance’s own factor.
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Last reviewed · How the calculations work