Head to head
Testosterone against Testosterone cypionate
The hormone and the ester most often prescribed in the United States. The ester does not change what testosterone does; it changes how fast it arrives, which is what dosing intervals and bloodwork timing are actually about.
Column A
TestosteroneTestosterone, the principal androgen
The best-evidenced hormone on this site. A 5,246-man randomised trial settled the cardiovascular question, and 36 randomised trials in 8,480 women cover the half of the population nobody talks about.
Column B
Testosterone cypionateTestosterone cypionate, long-chain injectable ester
The most prescribed injectable testosterone in the United States. Its eight-day half-life is why a single weekly shot produces a peak and a crash, and why splitting the same total flattens the curve.
Side by side, on the facts we can check
| Attribute | Testosterone | Testosterone cypionate |
|---|---|---|
| Category | Hormone | Hormone |
| FDA status | FDA-approved for male hypogonadism in multiple formulations. Schedule III controlled substance in the United States. No testosterone product is approved for women in the United States, which is a documented gap rather than a judgement on the evidence. | FDA-approved as Depo-Testosterone for male hypogonadism. Schedule III controlled substance. Not approved for women or for age-related low testosterone in men with normal levels. |
| Half-life | Free testosterone itself clears in minutes to hours. What determines dosing is the ester: cypionate and enanthate run roughly eight days, propionate under a day, and undecanoate several weeks. The ester pages cover what that means in practice. | Roughly 8 days. That single number is the argument: at an eight-day half-life, a fortnightly interval spans nearly two half-lives, so levels at the end of the cycle are a fraction of the peak. |
| Molecular weight | 288.4 Da. A steroid, not a peptide. | 412.6 Da. A steroid ester, not a peptide. |
| Mechanism | A 19-carbon steroid synthesised from cholesterol, mainly in the Leydig cells of the testis under luteinising hormone control, and in smaller amounts by the ovary and adrenal in women. It acts directly on the androgen receptor, a nuclear receptor that binds DNA and alters transcription. Two conversions matter clinically: 5-alpha-reductase converts it to dihydrotestosterone, a more potent androgen responsible for much of the effect on scalp hair and prostate, and aromatase converts it to oestradiol, which is responsible for much of its effect on bone, mood and libido in men. Exogenous testosterone suppresses luteinising hormone and follicle-stimulating hormone through negative feedback, which is why it reduces sperm production and testicular size. | Testosterone esterified at the 17-beta hydroxyl with cyclopentylpropionic acid, which makes it lipophilic enough to remain in an oil depot at the injection site. Tissue esterases cleave the ester gradually to release free testosterone, so the ester chain length governs the release rate rather than the activity. Once cleaved, the hormone is identical to endogenous testosterone and acts at the androgen receptor, with the same conversions to dihydrotestosterone by 5-alpha-reductase and to oestradiol by aromatase. Peak-to-trough variation across a dosing interval is a property of the ester and the interval, not of the molecule's potency. |
| Human studies cited | 2 | 1 |
| Legal status, US | FDA-approved, prescription only | FDA-approved, prescription only |
Frequently asked questions
What is the difference between Testosterone and Testosterone cypionate?
Testosterone: The best-evidenced hormone on this site. A 5,246-man randomised trial settled the cardiovascular question, and 36 randomised trials in 8,480 women cover the half of the population nobody talks about. Testosterone cypionate: The most prescribed injectable testosterone in the United States. Its eight-day half-life is why a single weekly shot produces a peak and a crash, and why splitting the same total flattens the curve.
Which has stronger research evidence, Testosterone or Testosterone cypionate?
This database does not grade compounds. It counts what was run in people: 2 of the 5 studies cited on the Testosterone profile were human work, against 1 of 2 for Testosterone cypionate. Those counts are of our own citation lists and understate any larger literature, and neither is a recommendation.
Are Testosterone and Testosterone cypionate FDA-approved?
Testosterone: FDA-approved for male hypogonadism in multiple formulations. Schedule III controlled substance in the United States. No testosterone product is approved for women in the United States, which is a documented gap rather than a judgement on the evidence.. Testosterone cypionate: FDA-approved as Depo-Testosterone for male hypogonadism. Schedule III controlled substance. Not approved for women or for age-related low testosterone in men with normal levels..
Reviewed Sep 2026. This page sets two published records side by side. It is educational, it is not medical advice, and it contains no dosing protocols or recommendations for personal use.