Reconstitution calculator
Enter your vial size, the bacteriostatic water you added, and your target dose. Get the exact concentration, draw volume, and insulin-syringe units.
Draw on syringe
—units
Volume
—mL
Concentration
—mcg/mL
Doses per vial
—
Vial lasts
—
Syringe fill visual
Check your draw
The math, exactly as this database defines it
concentration (mcg/mL) = vial_mg × 1000 ÷ water_mL
volume (mL) = dose_mcg ÷ concentration
units (U-100) = volume_mL × 100
doses per vial = floor(vial_mcg ÷ dose_mcg)
Concentration is reported to 1 decimal, volume to 3 decimals, and units to 1 decimal — matching the original CFPS Research calculator output precisely. A U-100 insulin syringe has 100 units per millilitre, so 0.25 mL is 25 units.
01Concentration reference table
| Vial size | Water added | Concentration | 250 mcg draw | 500 mcg draw |
|---|---|---|---|---|
| 2 mg | 1 mL | 2,000 mcg/mL | 12.5 u | 25.0 u |
| 2 mg | 2 mL | 1,000 mcg/mL | 25.0 u | 50.0 u |
| 5 mg | 1 mL | 5,000 mcg/mL | 5.0 u | 10.0 u |
| 5 mg | 2 mL | 2,500 mcg/mL | 10.0 u | 20.0 u |
| 5 mg | 3 mL | 1,666.7 mcg/mL | 15.0 u | 30.0 u |
| 10 mg | 1 mL | 10,000 mcg/mL | 2.5 u | 5.0 u |
| 10 mg | 2 mL | 5,000 mcg/mL | 5.0 u | 10.0 u |
| 10 mg | 3 mL | 3,333.3 mcg/mL | 7.5 u | 15.0 u |
| 10 mg | 5 mL | 2,000 mcg/mL | 12.5 u | 25.0 u |
| 15 mg | 3 mL | 5,000 mcg/mL | 5.0 u | 10.0 u |
| 20 mg | 2 mL | 10,000 mcg/mL | 2.5 u | 5.0 u |
| 30 mg | 3 mL | 10,000 mcg/mL | 2.5 u | 5.0 u |
02Practical notes
Choosing your water volume
- Aim for draws between 10 and 50 units — small enough to fit the syringe, large enough to measure accurately.
- If your draw is under 5 units, add more water. If it exceeds your syringe, use less.
- Bigger vials (10 mg+) usually pair with 2–3 mL of water; small 2 mg vials often use 1 mL.
Handling
- Direct water down the vial wall, not onto the powder pellet.
- Swirl gently to dissolve; never shake a peptide vial.
- Once reconstituted, store refrigerated and track your own expiry window.
For step-by-step reconstitution technique, see the complete reconstitution guide, and why vial volume changes your dosing math.
Research and educational use onlyNothing on this site is medical advice, a prescription, or a recommendation for human use. Compounds documented here are research chemicals. Consult a qualified clinician before making any health decision.