How many rods are in the human retina?

• A. Six million
• B. 120 million
• C. 1 million
• D. 60 million

Answer: (B)

Rods are the photoreceptors specialized for vision in dim light and for detecting motion; there are far more of them than cones in the human retina. The typical count is about 120 million rods, which far outnumbers the roughly 6 million cones. This large rod population is concentrated mainly in the peripheral retina, giving broad, sensitive, low-light vision, while the central retina (the fovea) is packed with cones for sharp, color-rich vision in bright light. So the number that best matches common anatomical measurements is around 120 million rods. The other options are not accurate: six million aligns more with cones, and one million or sixty million are well off the actual rod count.