Testosterone Cypionate vs Enanthate
This is the classic TRT question, and the honest answer is that the two are far more alike than different. Both deliver testosterone; the ester just changes the release curve slightly.
Side by side
| Testosterone Cypionate | Testosterone Enanthate | |
|---|---|---|
| Class | Testosterone esters | Testosterone esters |
| Form | Injection | Injection |
| Half-life | ≈ 8 days (192 h) | ≈ 7 days (168 h) |
| Storage | Room temperature | Room temperature |
| Dose units | mg, ml | mg, ml |
| FDA status | Approved | Approved |
Facts from the Stack compound library. See the full pages: Testosterone Cypionate · Testosterone Enanthate.
How they differ
The ester
Cypionate has an 8-carbon ester; enanthate has 7. That single carbon makes cypionate release marginally slower and gives it a slightly longer half-life.
Half-life in practice
The difference is small — both are measured in days, and most protocols inject on the same cadence regardless. For tracking purposes they behave the same: log the date, the dose and the site.
Availability
Cypionate is the most commonly prescribed injectable testosterone in the US; enanthate is more common elsewhere. Neither distinction affects how you'd log it.
Site rotation matters more than the ester
With any oil-based IM or subq testosterone, rotating sites and recording where you injected does more for a clean experience than the cypionate-vs-enanthate choice.
Tracking either one
Whichever you log, the workflow is the same in Stack: add it once, set the schedule, and let the app handle reminders, supply projection and an "in your system" curve from the half-life. Run both? Group them into one protocol you can pause together.
Track your stack in Stack
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Get the appLast reviewed 2026-06-11