VialLog

THE VIALLOG TOOLKIT

Free reconstitution calculator.

Make sense of mg, mL, and syringe units. Enter your confirmed values to see the math clearly.

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RECONSTITUTION CALCULATOR

Let’s do the math.

Use the total mass, not a concentration in mg/mL.

Use the final volume from the product or pharmacy instructions. Diluent added may not equal final volume.

All three sizes use the same U-100 scale: 100 units = 1 mL.

YOUR RESULTS

Your calculated result

Volume— mL
Concentration— mg/mL

Fill in your vial details. Your conversion appears here automatically.

U-100 syringe100 units · 1 mL
020406080100
Enter your values to see the calculated position
A calculation, not a dose recommendation.

Use an amount already specified by your clinician or pharmacist. Confirm your concentration, volume, and syringe markings before use. This tool does not select a diluent or tell you how to prepare a medication.

UNDERSTAND THE MATH

Three steps.
Every unit accounted for.

This peptide reconstitution calculator converts an entered mass and final volume into concentration, then converts your target amount into a volume. It does not recommend a compound or dose.

  1. Find the concentrationTotal vial amount (mg) ÷ final volume (mL) = mg/mL
  2. Convert the target amount to volumeTarget amount (mg) ÷ concentration (mg/mL) = mL
  3. Convert volume to U-100 unitsVolume (mL) × 100 = U-100 syringe units

THE FORMULA IN PRACTICE

A worked arithmetic example

10 mgVial amount
2 mLFinal volume
5 mg/mLConcentration

For an imaginary vial containing 10 mg in a final volume of 2 mL, concentration is 5 mg/mL. A target amount of 0.5 mg (500 mcg) corresponds to 0.1 mL, or 10 U-100 units.

These numbers illustrate the formula only. They are not preparation or dosing instructions.

Reconstitution calculator questions

Is this reconstitution calculator free?

Yes. The web calculator is free to use, with no account, email address, or app download required. Your calculator entries stay in this page and are not sent to VialLog.

How do I calculate reconstitution concentration?

Divide the total mass in the vial in milligrams by the final solution volume in milliliters. The result is concentration in mg/mL. Use the confirmed final volume: for some products, powder displacement means it differs from the amount of diluent added.

How do I convert mg to syringe units?

First divide the instructed amount in mg by concentration in mg/mL to get mL. For a U-100 syringe only, multiply mL by 100. Milligrams cannot be converted to syringe units without knowing the concentration.

Are 30-unit and 50-unit syringes a different scale?

A 30-unit, 50-unit, or 100-unit U-100 syringe has the same scale: 100 units per mL. The barrel capacity differs. Check the U-100 label; this calculator does not support U-40 syringes or medication-specific international units (IU).

Can this choose how much water or which dose I should use?

No. It only performs arithmetic on the values you enter. Your product instructions or pharmacist must specify the diluent, preparation method, final volume, storage, and dose. A calculation does not establish that a product is suitable for human use.

Does this work for a ready-to-use GLP-1 medication?

Do not add diluent to a ready-to-use medication or use this tool to convert pen clicks. Follow its label and your pharmacist’s instructions. If your pharmacy supplied a solution with a labeled concentration, ask them to confirm the prescribed volume and syringe markings.

BEYOND THE CALCULATION

Keep your routine together.

Explore VialLog for dose history, vial records, and reminders.

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