What color is sperm?
The color of semen is determined by its constituent components.
Normal semen appears grayish-white or milky-white and opaque. Freshly ejaculated semen has a viscous, jelly-like consistency and typically begins to liquefy within 5 minutes—this process is known as semen liquefaction—and is usually complete within 15–30 minutes.
A pale yellow hue may occur after prolonged abstinence, resulting in slight color variation and increased viscosity—this is considered normal. However, yellow semen may also indicate inflammation of the male reproductive tract; under microscopic examination, numerous pus cells may be observed, strongly suggesting purulent infection of the prostate or seminal vesicles.

If semen appears red or light red—or occasionally brownish-red or soy-sauce-colored—and microscopic examination reveals numerous red blood cells, this condition is commonly referred to as “hematospermia” (blood in semen). Hematospermia most frequently results from seminal vesiculitis or prostatitis. In addition to bleeding, some individuals may experience associated pain.
Occasionally, vigorous or overly forceful sexual activity may cause minor trauma and capillary rupture in the genital organs, leading to transient hematospermia—a benign, self-limiting physiological phenomenon that resolves spontaneously.