Last updated: June 2026
Testosterone Propionate Dosage Calculator
Quick answer: A 100 mg/week dose over 3.5 shots from a 100 mg/mL vial is 0.286 mL (28.6 units) per shot, ≈ 84 mg active hormone/week. mL = (weekly mg ÷ shots) ÷ mg/mL.
Injectable ester — about 84% of each mg is Testosterone; the calculator converts dose → mL, units and active mg. Aromatises: Yes. Liver-strain (17α-alkylated): No. Half-life: ≈ 20 hours (drug monograph; reported values cluster 19–48 h).
About this calculator
Testosterone propionate is the short-ester testosterone. With the smallest ester here, about 84% of each milligram is testosterone, but its short half-life means frequent injections. This calculator converts a weekly dose into mL and U-100 units and shows the active-testosterone milligrams.
Propionate is the fastest-acting common testosterone ester, usually supplied at 100 mg/mL. Its short action means it is injected every day or two rather than weekly.
How the injection-volume maths works
The small propionate ester is only a sixth of the molecule’s weight, so 100 mg delivers about 84 mg of testosterone (288.4 ÷ 344.5) — the highest active fraction of the testosterone esters here.
How to use this calculator
Enter your weekly dose, the concentration printed on your vial (mg/mL), and how many injections per week. The result updates instantly with the mL to draw, the U-100 syringe units, and the active-hormone milligrams delivered.
Worked examples
Weekly dose: 100 mg · Concentration: 100 mg/mL · Injections/week: 3.5
28.57 mg/shot ÷ 100 = 0.286 mL (28.6 units) · active ≈ 84 mg/week
Weekly dose: 150 mg · Concentration: 100 mg/mL · Injections/week: 7
21.43 mg/shot ÷ 100 = 0.214 mL (21.4 units) · active ≈ 126 mg/week
Testosterone Propionate dose chart
Common doses at 100 mg/mL, 2 injections/week (each row is the calculator’s arithmetic worked out):
| Weekly dose | mL/shot | Units | Active/week |
|---|---|---|---|
| 50 mg | 0.25 mL | 25 | 42 mg |
| 75 mg | 0.375 mL | 37.5 | 63 mg |
| 100 mg | 0.5 mL | 50 | 84 mg |
| 150 mg | 0.75 mL | 75 | 126 mg |
| 200 mg | 1 mL | 100 | 168 mg |
| 300 mg | 1.5 mL | 150 | 252 mg |
Half-life & clearance
Illustrative single-dose elimination by half-life (t½ ≈ 0.83 days). Each marker is one half-life; after ~5 the dose is essentially cleared. For an oil depot the real rise-and-fall is slower (absorption-limited release), so treat this as a timing reference, not a blood-level prediction.
With a ~20-hour half-life it clears within a couple of days, which is why it is injected far more often than the long esters. The figure is monograph-grade; reported values vary by method (roughly 19–48 hours), so treat it as a guide.
How to interpret your result
The result is the volume to draw per injection and its mark on a U-100 syringe. The active-hormone figure shows how much actual Testosterone Propionate that ester delivers — useful when comparing esters or switching concentrations. The half-life figure is a pharmacokinetic timing reference only.
Aromatisation, liver & monitoring
It is testosterone, so it aromatises to estradiol like the longer esters. Not 17α-alkylated, so no oral-style liver strain — the practical trade-off is injection frequency, not liver load.
Common mistakes
Dosing propionate weekly like a long ester is the classic error — the short half-life means levels swing sharply between infrequent shots. The maths per shot is the same; the schedule is not.
Testosterone Propionate at a glance
| Property | Testosterone Propionate |
|---|---|
| Form | Injectable (oil/suspension) |
| Active fraction | 0.84 (esterFactor) |
| Half-life | ≈ 20 hours (drug monograph; reported values cluster 19–48 h) |
| Aromatises | Yes — the testosterone parent aromatises to estradiol. |
| Liver (17α-alkylated) | No (not 17α-alkylated). |
| Approx. detection | ~2–3 weeks. |
Frequently asked questions
Related guides
Other compounds
Other calculators
References
- PubChem — testosterone propionate (molecular weight), CID 5995
- PubChem — testosterone (molecular weight), CID 6013
- Pharmacology of testosterone replacement therapy preparations. Transl Androl Urol 2016
- Kicman AT. Pharmacology of anabolic steroids. Br J Pharmacol 2008;154(3):502–521
Every citation URL was verified to return HTTP 200. Citations are provided for transparency and education and do not imply the cited authors or bodies endorse this tool. Anabolic steroid use carries real health risks — always consult a qualified clinician.
How this is calculated
For injectables the calculator divides your weekly dose by the number of injections, then by the vial concentration, to get the mL per shot — and multiplies by 100 for U-100 syringe units (1 mL = 100 units). The active-hormone milligrams are the dose multiplied by the esterFactor (the parent hormone’s molecular weight divided by the full ester’s molecular weight, both from PubChem). For orals it divides the daily dose by your doses-per-day and tablet strength to get tablets per dose. Half-life timing uses ke = ln2 ÷ t½ and the ~5-half-life rule of thumb for steady state and clearance. It is arithmetic only — nothing you enter is stored or sent anywhere, and the result is not medical advice or an endorsement of anabolic steroid use.