Semaglutide Calculator
Enter your vial size and starting dose — get exact syringe units plus a full 12-week titration schedule you can follow.
Your Titration Schedule
Weekly injection. Hold each step for 4 weeks before stepping up, or longer if side effects need to settle. If you're happy with weight loss at a lower step, you can stay there.
| Week | Dose | Units | mL | Stage |
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Track your titration automatically
PepStackr tracks every injection, reminds you when it's time for your weekly shot, and alerts you before your vial expires. It even visualizes your blood level between doses. Free to start.
Create Free AccountHow Semaglutide Dosing Works
Semaglutide is a once-weekly GLP-1 receptor agonist. The half-life is long — about 7 days — which means a single weekly injection produces stable blood levels. Doses are measured in milligrams (mg), not micrograms, because semaglutide is active at much lower nanomolar concentrations than research peptides but is prescribed in larger milligram amounts.
The Standard Titration
The Wegovy (weight management) label specifies this escalation schedule:
- Weeks 1–4: 0.25 mg weekly
- Weeks 5–8: 0.5 mg weekly
- Weeks 9–12: 1.0 mg weekly
- Weeks 13–16: 1.7 mg weekly
- Week 17 onward: 2.4 mg weekly (maintenance)
The reason for the slow ramp: semaglutide's GI side effects (nausea, constipation, reflux) are heavily dose-dependent. Starting at 0.25mg and climbing gives the gut time to adapt at each step. Skipping steps is usually a one-way ticket to severe nausea.
Compounded vs Brand Name
Branded semaglutide (Wegovy, Ozempic) ships in prefilled pens with fixed doses. Compounded semaglutide ships as a lyophilized powder in a vial — you reconstitute with bacteriostatic water, then draw your dose on an insulin syringe. The active ingredient and dose are identical; the difference is the delivery mechanism and price.
How Much to Add?
There's no "correct" BAC water volume. Pick one that makes your starting dose land on a round number of units. Common choices:
- 5mg vial + 2mL water → 2.5 mg/mL → 0.25 mg = 10 units
- 5mg vial + 1mL water → 5 mg/mL → 0.25 mg = 5 units
- 10mg vial + 2mL water → 5 mg/mL → 0.25 mg = 5 units
- 10mg vial + 4mL water → 2.5 mg/mL → 0.25 mg = 10 units
Reaching Steady State
With a 7-day half-life and weekly dosing, it takes about 4–5 weeks to reach 95% of steady state at any given dose. That's why each titration step is 4 weeks — it gives the drug time to fully accumulate before you evaluate whether to step up.
When to Not Step Up
Common reasons to hold at a lower dose:
- You're losing weight at a steady 0.5–1% of body weight per week — that's the target range; stepping up doesn't necessarily mean faster results
- GI side effects from the previous step-up haven't fully resolved
- You're happy with where you are and appetite suppression is working