Compare · SARM
S23 vs YK-11
Both are sarm compounds. Here's how they line up on the evidence — graded the same way.
| S23 | YK-11 | |
|---|---|---|
| Evidence | Animal only | Animal only |
| Class | SARM | SARM |
| Summary | S23 is a synthetic selective androgen receptor modulator (SARM) — not a peptide — studied only in rodents as a male contraceptive candidate. There are no human trials, and it is an unapproved drug banned in sport. | YK-11 is a synthetic steroidal SARM marketed for muscle growth, but its claimed human benefits rest entirely on cell-culture data — there are no human trials, and it is an unapproved drug banned in sport. |
| Full profile → | Full profile → |
S23
S23 is a synthetic selective androgen receptor modulator (SARM) — explicitly not a peptide — that binds the androgen receptor and acts as a tissue-selective agonist, aiming for anabolic effects in muscle and bone with relatively less prostate/seminal activity. It was designed as a male…
YK-11
YK-11 is a synthetic compound sold as a SARM (selective androgen receptor modulator) and promoted for muscle growth. Despite the marketing, it is not a peptide — it is a steroidal molecule built on a 19-norandrostane backbone. Its reputation as a uniquely powerful "myostatin-inhibiting SARM" rests…