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Peptide Calculator

Convert known quantities into concentration, mL and U-100 syringe units.

Free to use. No account.
Your numbers stay in your browser.

Reconstitution & unit conversionView result ↓
Enter your known quantities

Syringe capacity

All options use the U-100 scale.

Capacity changes the scale, not the concentration. About U-100 units ↗

mg
mL
mcg

Input shortcuts only, not recommended amounts.

Example resultU-100

100 mcg corresponds to

2units on a U-100 syringe

0.02 mL of solution

Concentration5 mg/mL

5,000 mcg/mL

051015202530

Illustrative U-100 scale · verify the graduations on your actual syringe.

Show the calculation

Concentration
5 mg ÷ 1 mL = 5 mg/mL

Volume for the entered amount
100 mcg ÷ 5,000 mcg/mL = 0.02 mL

U-100 scale
0.02 mL × 100 units/mL = 2 units

Theoretical whole draws
50 complete draws, 0 mcg remaining. Excludes losses and says nothing about shelf life.

Example values only. Enter your own known values to calculate.

Assumes the water added approximates the final solution volume. Mathematical conversions only; this tool does not determine a dose, solvent suitability, or container capacity. Read the methodology.

How to use the calculator

Read the full guide

  1. Choose your syringe

    Select its total capacity. Every option uses the U-100 scale.

  2. Enter the vial amount

    Use the amount in mg from your actual vial label.

  3. Add the volume

    Enter the added water or your known final solution volume.

  4. Enter your target

    Use your already-known amount. Read the corresponding volume and units.

Related calculators

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BAC water calculator

Work backwards from a target concentration or a known amount and U-100 mark.

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mg / mcg converter

Switch between milligrams and micrograms. Keep every unit in its place.

Convert units

Calculators by peptide

Find a focused calculator with vial amount options and specific input explanations.

Find your calculator

Check every conversion.

Concentration connects the mass in your vial to the volume on the scale. Every result shows the arithmetic behind it.

Our methodology

A worked example

Concentration
5 mg ÷ 1 mL = 5 mg/mL
Volume for 100 mcg
100 ÷ 5,000 mcg/mL = 0.02 mL
U-100 scale
0.02 mL × 100 units/mL = 2 units

Illustrative inputs, not a recommended amount.

Common questions

The units, assumptions and limits behind your result.

Explore the guides
How do I use this peptide calculator?

Choose your U-100 syringe capacity, enter the mass in the vial, enter the added water or known final solution volume, and enter your already-known target amount. The calculator returns concentration, mL and U-100 units.

Does the calculator tell me what dose to use?

No. You supply the target amount from your source instructions. The tool performs arithmetic and does not choose a dose, schedule, solvent or product.

Why do mg, mcg, mL and units give different numbers?

mg and mcg measure mass: 1 mg = 1,000 mcg. mL measures volume. U-100 syringe units are volume marks: 100 units = 1 mL. A mass-to-volume conversion also needs the solution concentration.

Does changing syringe size change the result?

Changing capacity alone does not change concentration, the required mL or the corresponding U-100 units. It changes the maximum scale and whether the calculated volume fits.

How much water should I add to a 10 mg or 20 mg vial?

Vial mass alone does not determine a unique water volume. You also need a known target concentration or a target amount and corresponding volume. Use the BAC water calculator to work backwards from those conditions.

Is this peptide calculator free?

Yes. The calculator and guides are available without an account. Calculations happen in your browser; the entered numbers are not sent to a calculation server.