ADAM wrote:According to Ollie's half-life post

Phenyl is 4.5 days

Iso 9 days

Could be right but I got mine from

http://www.steroidcalc.comWhich I think are the new half-lifes found to be more accurate , think Robbie or Inception posted similar a few months back too.

The old list most sites cite are actually the active lives of the compound not the half-lives from what I gather below.

This also explains why people that dose Sus 1-2 times per week experience big dips/not as good results compared to 3 times per week and always complain of unstable bloods.

About

None of the information on this site is guaranteed to be accurate. Use at your own risk.

The formula used for calculating the rate of compound release at a given day t is:

λ * N(t)

Where λ is the decay constant equal to ln(2)/h, h being the half life of the compound given in days; and N(t) is the half-life equation given by:

N(t) = n * e^(-t/λ)

Where n is the original dose of the compound in mg and t is given in days.

Terminal Half-lives

Testosterone Propionate: 0.8 days

Testosterone Phenylpropionate: 1.5 days

Testosterone Isocaproate: 4.0 days

Testosterone Enanthate: 4.5 days

Testosterone Cypionate: 5.0 days

Testosterone Decanoate: 7.5 days

Testosterone Undecanoate: 20.9 days

Trenbolone Acetate: 1.0 days

Trenbolone Enanthate: 4.5 days

Masteron Propionate: 0.8 days

Masteron Enanthate: 4.5 days

Nandrolone Phenylpropionate: 1.5 days

Nandrolone Decanoate: 7.5 days

Equipoise: 14.0 days

Primobolan Oral: 5 hours

Primobolan Injectable: 4.5 days

Halotestin: 7 hours

Anadrol: 14 hours

Dianabol: 5 hours

Turinabol: 16 hours

Winstrol Oral: 8 hours

Winstrol Injectable: 1.0 days

Anavar: 10 hours

Superdrol: 10 hours

These half-lives are approximations, and may vary slightly depending on injection site, carrier oil, and other factors.

Note: A different list of half-lives is often copy and pasted on various sites, claiming that, for example, the half-life for the propionate ester is 4.5 days and that the half-life for the enanthate ester is 10.5 days. This list is incorrect, and is the result of flawed calculations many years ago. See the "References" section for more information.

Active Dose

Injectable steroids are typically bound by esters, which comprise a portion of the steroid's weight. Because of this, 100mg of, for example, testosterone enanthate does not equate to 100mg of pure testosterone. In this case, there is only 70mg of testosterone being injected, and the remaining 30mg is the enanthate ester. This is taken into account when plotting cycles on this site, as different esters have different weights. Listed below is the percentages of the actual hormones for different steroid and ester combinations:

Testosterone Propionate: 80%

Testosterone Phenylpropionate: 66%

Testosterone Isocaproate: 72%

Testosterone Enanthate: 70%

Testosterone Cypionate: 69%

Testosterone Decanoate: 62%

Testosterone Undecanoate: 61%

Trenbolone Acetate: 87%

Trenbolone Enanthate: 70%

Masteron Propionate: 80%

Masteron Enanthate: 70%

Nandrolone Phenylpropionate: 67%

Nandrolone Decanoate: 64%

Equipoise: 61%

Primobolan Oral: 100%

Primobolan Injectable: 70%

Halotestin: 100%

Anadrol: 100%

Dianabol: 100%

Turinabol: 100%

Winstrol Oral: 100%

Winstrol Injectable: 87%

Anavar: 100%

Superdrol: 100%

References

Behre HM, Nieschlag E. 1998 Comparative pharmacokinetics of testosterone esters. In: Nieschlag E, Behre HM, eds. Testosterone: Action, Deficiency, Substitution, ed 2. Berlin: Springer-Verlag; 329–348.