Calculator · Semaglutide
Free, no account, runs in your browser. Built for compounded semaglutide where vial concentration changes pharmacy to pharmacy. Worked examples for 5 mg and 10 mg vials below.
Inputs
Punch in the vial size, the BAC water you reconstituted with, and your target dose. The math runs live.
The total mg in the vial. Common: 5, 10, 15, 30 mg.
The bacteriostatic water volume your pharmacy specified. Usually 1, 2, or 3 mL.
The mg per injection from your prescription.
Quick presets
Draw this
10.0 units
On a U-100 insulin syringe.
Formula
dose volume = 0.25 mg ÷ (5 mg ÷ 2 mL)
= 0.25 mg ÷ 2.50 mg/mL
= 0.100 mL = 10.0 units
Save this calculation
Get Titrate to save this dose, anchor side-effects to where you are on the plasma curve, and catch the next BAC-water change at refill.
7-day Pro trial · iOS 17+
The math
dose volume (mL) = target dose (mg) ÷ (vial mg ÷ BAC water mL)
On a U-100 insulin syringe, 1 unit equals 0.01 mL. Multiply dose volume in mL by 100 to get units. The single most common error is treating “units” as “milligrams” — they measure different things, and they only line up coincidentally at one specific concentration.
Wegovy / Ozempic dose ramp
Every 4 weeks, the dose steps up if tolerated. Each step is held for the minimum 4 weeks so the previous step reaches steady-state before stacking on more semaglutide.
| Week | Dose | Notes |
|---|---|---|
| Weeks 1–4 | 0.25 mg | Starter. Sub-therapeutic by design; GI adaptation step. |
| Weeks 5–8 | 0.5 mg | First therapeutic step. ~40% of users see appetite suppression. |
| Weeks 9–12 | 1.0 mg | Common long-term maintenance dose. |
| Weeks 13–16 | 1.7 mg | Wegovy-only step (Ozempic skips here to 2.0 mg). |
| Week 17+ | 2.4 mg | Wegovy max. Ozempic max is 2.0 mg. |
Source: Wegovy and Ozempic FDA labels. Full schedule with hold-vs-advance criteria: semaglutide dose schedule guide.
Worked examples
The vials your pharmacy ships are typically 5 mg or 10 mg. Reconstitution volume varies — these are the combinations users actually receive.
| Vial + BAC water | Concentration | Target dose | Dose volume | U-100 units |
|---|---|---|---|---|
| 5 mg / 1 mL BAC | 5.00 mg/mL | 0.25 mg | 0.05 mL | 5 units |
| 5 mg / 1 mL BAC | 5.00 mg/mL | 0.5 mg | 0.10 mL | 10 units |
| 5 mg / 1 mL BAC | 5.00 mg/mL | 1.0 mg | 0.20 mL | 20 units |
| 5 mg / 2 mL BAC | 2.50 mg/mL | 0.25 mg | 0.10 mL | 10 units |
| 5 mg / 2 mL BAC | 2.50 mg/mL | 1.0 mg | 0.40 mL | 40 units |
| 5 mg / 2.5 mL BAC | 2.00 mg/mL | 1.0 mg | 0.50 mL | 50 units |
| 10 mg / 2 mL BAC | 5.00 mg/mL | 1.0 mg | 0.20 mL | 20 units |
| 10 mg / 2 mL BAC | 5.00 mg/mL | 2.4 mg | 0.48 mL | 48 units |
Compounded semaglutide context
Compounded semaglutide is the same active molecule as Wegovy and Ozempic, prepared by a 503A pharmacy instead of Novo Nordisk. The molecule is identical. What differs is the vial concentration — and that's the one variable that can quietly cut your dose in half on a refill.
A 5 mg vial reconstituted in 1 mL gives 5 mg/mL. The same 5 mg vial reconstituted in 2 mL gives 2.5 mg/mL. Your prescribed dose in milligrams is the same. Your dose volume in milliliters — and the units you draw — are not.
Every refill, re-read the pharmacy label. If the BAC water volume changed, your unit count changes. The calculator above catches it; muscle memory does not.
Beyond-use date is typically 28 days post-reconstitution under refrigeration. Additives are sometimes included — B6, B12, glycine, L-carnitine — which don't change the semaglutide math but do change side-effect attribution. The FDA-approved 0.25 → 0.5 → 1.0 → 1.7 → 2.4 mg titration ladder still applies; compounded does not mean weaker.
Full guide: Compounded semaglutide — what it is, what to verify, what to track.
Common questions
Track what you reconstitute
Dose log, side-effect anchoring, plasma-decay charts, multi-compound stacks. Free to start, on-device by design.