Enter vial size (5–60 mg), BAC water volume, and weekly dose to get concentration, syringe units to draw, and doses per vial. Includes the 6-tier titration schedule (2.5–15 mg weekly), vial size comparison, and syringe capacity warnings. Verify tirzepatide quality with independent lab test data on Peptigrity.
Educational tool for research use. Not medical advice — it calculates what you enter, it doesn't recommend a dose.
Draw the syringe up to
That's one 2.5 mg dose. Add 2 mL of water to your 10 mg vial first.
| Step | Dose | Draw on a U-100 | Doses per vial |
|---|---|---|---|
| Tier 1 (start) | 2.50 mg | 50 units | 4 |
| Tier 2 | 5 mg | 100 units | 2 |
| Tier 3 | 7.50 mg | 150 units | 1 |
| Tier 4 | 10 mg | 200 units | 1 |
| Tier 5 | 12.50 mg | 250 units | — |
| Tier 6 (max) | 15 mg | 300 units | — |
Tap any row to load that dose into the calculator above.
The tiers below are the escalation steps stated in the US prescribing information — 2.5 mg weekly, rising by 2.5 mg every 4 weeks to a maximum of 15 mg. They are reproduced here as the reference points the syringe-unit columns are calculated against, not as a protocol to follow. Peptigrity is not affiliated with or endorsed by any manufacturer.
| Tier | Weekly dose | Weeks | @ 5 mg/mL | @ 10 mg/mL | @ 15 mg/mL |
|---|---|---|---|---|---|
| Tier 1 (start) | 2.5 mg | Weeks 1–4 | 50 u | 25 u | ~17 u |
| Tier 2 | 5 mg | Weeks 5–8 | 100 u | 50 u | ~33 u |
| Tier 3 | 7.5 mg | Weeks 9–12 | Exceeds | 75 u | 50 u |
| Tier 4 | 10 mg | Weeks 13–16 | Exceeds | 100 u | ~67 u |
| Tier 5 | 12.5 mg | Weeks 17–20 | Exceeds | Exceeds | ~83 u |
| Tier 6 (max) | 15 mg | Week 21+ | Exceeds | Exceeds | 100 u |
At 5 mg/mL concentration (10 mg vial + 2 mL BAC water), doses above 5 mg exceed a standard 100-unit syringe's capacity. Users titrating beyond 5 mg must increase the concentration (use less BAC water) or split the dose across 2 draws. The calculator above flags syringe capacity warnings automatically.
| Vial size | @ 2.5 mg/wk | @ 5 mg/wk | @ 10 mg/wk | @ 15 mg/wk | Best for |
|---|---|---|---|---|---|
| 5 mg | 2 weeks | 1 week | — | — | Trial / starting dose |
| 10 mg | 4 weeks | 2 weeks | 1 week | — | Tiers 1–2 |
| 15 mg | 6 weeks | 3 weeks | 1.5 weeks | 1 week | Single-tier coverage |
| 30 mg | 12 weeks | 6 weeks | 3 weeks | 2 weeks | Multi-week protocols |
| 60 mg | 24 weeks | 12 weeks | 6 weeks | 4 weeks | Extended protocols |
Shelf life constraint: Reconstituted tirzepatide lasts approximately 28 days. Larger vials may outlast the stability window. Reconstitute only what you need for 4 weeks. For price comparisons, use the cost-per-dose calculator.
| Factor | Tirzepatide | Semaglutide |
|---|---|---|
| Receptor targets | Dual: GIP + GLP-1 | GLP-1 only |
| Starting dose | 2.5 mg weekly | 0.25 mg weekly |
| Maintenance range | 5–15 mg weekly | 1.0–2.4 mg weekly |
| Maximum dose | 15 mg weekly | 2.4 mg weekly (Wegovy) |
| Titration steps | +2.5 mg every 4 weeks | +0.25–0.5 mg every 4 weeks |
| Common vial sizes | 5, 10, 15, 30, 60 mg | 2, 3, 5, 10 mg |
At 5 mg/mL (10 mg vial + 2 mL BAC water), 2.5 mg = 50 units. At 10 mg/mL (10 mg vial + 1 mL BAC water), 2.5 mg = 25 units. At 15 mg/mL, 2.5 mg = approximately 17 units. Use the calculator above with your specific vial and BAC water volume for the exact draw.
1 mL produces 10 mg/mL — suitable for doses up to 10 mg in a single 100-unit draw. 2 mL produces 5 mg/mL — easier to measure small starting doses (2.5 mg = 50 units) but exceeds syringe capacity above 5 mg. Choose based on the tier being calculated.
Reconstituted tirzepatide stored at 2–8°C (standard refrigerator) remains stable for approximately 28 days. Unreconstituted lyophilised powder stored at −20°C maintains integrity for 3–6 months.
Both contain the same 39-amino-acid dual GIP/GLP-1 receptor agonist. Branded tirzepatide is an FDA-approved prescription medicine supplied as a pre-filled pen. Compounded tirzepatide is produced by pharmacies under FDA 503A/503B regulations as lyophilised powder requiring reconstitution — which is what this calculator is for.
Divide the dose (in mg) by the concentration (in mg/mL), then multiply by 100. Example: 5 mg ÷ 10 mg/mL = 0.5 mL × 100 = 50 units. The calculator performs this conversion automatically.
At 2.5 mg/week: 12 doses. At 5 mg/week: 6 doses. At 10 mg/week: 3 doses. At 15 mg/week: 2 doses. However, reconstituted tirzepatide is stable for approximately 28 days — so plan reconstitution in portions if your protocol extends beyond that.