What decanoate is
Decanoate is the longest ester in general blend use. A ten-carbon chain pushes the half-life beyond a week, which is what gives Sustanon 250 and Test 400 their extended tail. It is almost never sold as a single-ester testosterone product.
- Ester chain
- 10-carbon (decanoic acid)
- Half-life
- Approximately 7.5 days.
- Testosterone fraction
- 64% by weight
- Per 100 mg of ester
- 64 mg of testosterone
- Presentation
- Oil solution, effectively always as a blend component.
- Storage
- Room temperature, protected from light.
Weight, and why it is not a detail
The long chain also means the lowest testosterone fraction of the common esters, at roughly 64 mg per 100 mg. In a blend, decanoate is the component that decides how long the preparation continues to release after the last injection, which matters more for interpreting a blend than the headline concentration does.
Where you meet it
Decanoate is the ester that does the quiet work in both major blends. It is the largest single fraction of Test 400, measured at 170.64 mg/ml and 155.16 mg/ml across two HPLC reports, and the largest fraction of Sustanon 250 at 100 mg of the 250. In both cases it is the component that determines the tail.
- Test 400 three at 400 mg/ml
- Sustanon 250 four at 250 mg/ml
Nearest esters
The closest reference points on the release curve.
Common questions
Why is decanoate in so many blends but never sold alone?
Its value is as the long component of a mixture. On its own a roughly 7.5 day half-life offers little over enanthate or cypionate while carrying less testosterone per milligram, at about 64%.
Which ester keeps working longest after the last injection?
Of the esters in common blends, decanoate. In both Test 400 and Sustanon 250 it is the fraction still releasing once the shorter esters have cleared.
How much testosterone is in Testosterone Decanoate?
About 64% by weight. 100 mg of testosterone decanoate contains roughly 64 mg of testosterone, the remainder being the ester chain.
Does this page give dosing information for Testosterone Decanoate?
No. This is a reference resource covering the ester, its release profile, its weight and its storage. It does not provide dosing protocols, administration schedules or medical advice.