Ester Clearance Calculator

Reference decay math from literature ester half-lives — remaining fraction after any interval and time to 5% or 1% of the starting amount.

Half-life in, clearance out.

Long-acting esters release hormone slowly and take weeks to clear. See how much of a compound remains at any point after the last dose, and when it falls to 5% or 1% — the standard research thresholds for "effectively cleared".

Est. half-life

— days

Remaining now

—

Time to 5% remaining

—

Time to 1% remaining

—

Reference decay curve (12-week window)

Clearance reference — time to 5% remaining

Compound	Est. half-life	≈ 5% clearance
Testosterone Enanthate	4.5 days	≈ 2.8 weeks
Testosterone Cypionate	8 days	≈ 4.9 weeks
Sustanon 250 (blend)	8 days	≈ 4.9 weeks
Trenbolone Acetate	2 days	≈ 1.2 weeks
Nandrolone Decanoate	15 days	≈ 9.3 weeks
Boldenone Undecylenate	14 days	≈ 8.6 weeks
Drostanolone Propionate	4.5 days	≈ 2.8 weeks
Methenolone Enanthate	10 days	≈ 6.2 weeks
Stanozolol (oral)	0.5 days	≈ 0.3 weeks
Oxandrolone (oral)	0.5 days	≈ 0.3 weeks
Methandrostenolone (oral)	0.5 days	≈ 0.3 weeks

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How it works

The math

Exponential decay

remaining = 100 × e^(−k·t), k = ln2 ÷ half-life

Each half-life halves the remaining amount: 1 → 50% → 25% → 12.5% → 6.25% → 3.1%. After five half-lives roughly 3% remains — the conventional "cleared" threshold in research protocols.

Example — nandrolone decanoate

With a ~15 day half-life, reaching 5% remaining takes ≈ 4.3 × 15 = 65 days (≈ 9.2 weeks). An acetate with a 2-day half-life clears to 5% in under 9 days. This is why ester choice dominates cycle timing.

Simplified single-compartment model with population-average half-life estimates. For laboratory research context only — not medical advice and not a drug-testing prediction.

FAQ

Frequently asked questions

What does 'time to 5% remaining' mean?

Under a first-order clearance model, the active amount of a compound decays by a fixed fraction per half-life. Five percent remaining corresponds to about 4.3 half-lives; one percent to about 6.6 half-lives.

Why are these estimates, not exact times?

Half-lives are population averages from published pharmacokinetic studies and vary substantially between individuals (metabolism, dose history, ester release kinetics). The model is for laboratory research context only.

Does this predict drug-test detection windows?

No. Detection windows depend on metabolites, testing method and cut-off thresholds — not just the parent compound's half-life. This tool models clearance math only.

How is the clearance curve drawn?

Undecylenate ester. Sustained-release anabolic standard.

CAS 13103-34-9

10mL vial · In stock

For laboratory research use only