Tirzepatide Dose Calculator: How Many Units in Your Syringe

Reference guide. Next Day Pharma supplies pre-filled, ready-to-use injection pens — there is nothing to mix, and no vials, powder or bacteriostatic water are involved. This article is published as general reference information only.

The most common mistake with tirzepatide is mis-reading the syringe. The medicine is measured in milligrams, your syringe is graduated in units, and the relationship between the two depends entirely on how much bacteriostatic water you added.

The quick rule

If you reconstitute a 10 mg tirzepatide vial with 2 ml of BAC water, the concentration is 5 mg/ml. On a standard U-100 insulin syringe, every 10 units equals 0.1 ml — so every 10 units = 0.5 mg.

Dose conversion chart

Dose	2 ml mix (5 mg/ml)	1 ml mix (10 mg/ml)
2.5 mg	50 units	25 units
5 mg	100 units	50 units
7.5 mg	2 × 75 units	75 units
10 mg	2 × 100 units	100 units
12.5 mg	n/a — too much volume	2 × 62 units
15 mg	n/a	2 × 75 units

Why most researchers choose 2 ml

Lower concentration means slightly higher injection volume but better dosing accuracy at low (2.5–5 mg) doses. As you titrate up, you can switch to a 1 ml mix to keep injection volumes small.

Skip the maths

Our peptide calculator handles every vial size, BAC water volume and target dose in a single tap. Bookmark it.

Frequently asked questions

What is a U-100 syringe?

A standard insulin syringe graduated so that 100 units equals 1 ml. The default for peptide use.

Can I dose half a unit?

Not reliably. If your dose requires sub-unit precision, use a lower concentration mix (more BAC water).

Why do my units not match someone else's?

Different BAC water volumes give different concentrations. Always check the mix ratio before comparing.

Is the calculator free?

Yes — peptide-calculator is free to use, no signup.

This guide is provided for informational purposes by Next Day Pharma. All peptides supplied are FOR RECONSTITUTION. Always consult a qualified healthcare professional before use.

Peptide catalogue

Melanotan II — £40.00 — 10mg of Melanotan II
Somatropin (HGH) — £60.00 — Somatropin (Human Growth Hormone)
Cagrilintide 10mg — £60.00 — 10mg of Cagrilintide
Epitathlon — £50.00 — 10mg of Epitathlon
PT-141 10mg — £40.00 — 10mg of PT-141
SLU-332 5mg — £65.00 — 5mg of SLU-332
CJC + Ipamorelin — £55.00 — 5mg CJC-1295 + 5mg Ipamorelin
5 Amino 1MQ 50mg — £60.00 — 50mg of 5 Amino 1MQ
SS-31 10mg — £40.00 — 10mg of SS-31
Semax 10mg — £40.00 — 10mg of Semax
Selank 10mg — £40.00 — 10mg of Selank
Ipamorelin 10mg — £40.00 — 10mg of Ipamorelin
Wolverine — £75.00 — 10mg of Wolverine
MOTS-C 20mg — £80.00 — 20mg of MOTS-C
Tesamorelin 20mg — £110.00 — 20mg of Tesamorelin
NAD+ 1000mg — £125.00 — 1000mg of NAD+
GLO 70mg — £70.00 — 70mg of GLO
KLOW 80mg — £90.00 — 80mg of KLOW
BPC-157 10mg — £40.00 — 10mg of BPC-157
TB500 10mg — £50.00 — 10mg of TB500
Retatrutide — £200.00 — Retatrutide
Tirzepatide — £180.00 — Tirzepatide
MT2 10mg (NEXT DAY TAN) — £50.00 — 10mg of Melanotan2
GHK-CU 100mg — £60.00 — 100mg of GHK-CU

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