The human body does not have one universally agreed-on “exact” muscle count, but most anatomy sources say there are a little over 600 named skeletal muscles, often rounded to about 650.

Why the number isn’t “exact”

Different experts and textbooks give slightly different totals because:

  • Some small muscles can be fused together in one person but separate in another, so counting them changes the total.
  • Some sources count only the main skeletal (movement) muscles, while others include tiny, obscure muscles (especially in the face, larynx, eyes, and pelvis).
  • Smooth and cardiac muscles are usually counted by organs or cells, not as individual muscles, so their “number” runs into the millions or more, not a neat single figure.

So when you see figures like 600 , 639 , or “about 700” muscles, they are using different counting rules, not describing different bodies.

Commonly cited muscle counts

  • “About 600 muscles”: A standard rounded figure in many health and education resources.
  • “Over 650 skeletal muscles”: Often used in medical and health articles that count more named skeletal muscles.
  • “Around 639 muscles”: A classic exam-style answer used in some biology curricula and quiz banks.
  • “Just under 700 named skeletal muscles”: A more expansive tally that includes many small, rarely discussed muscles.

If someone asks “how many muscles are in the human body exactly,” the most honest short answer is: there are a bit over 600 named skeletal muscles, commonly cited as roughly 650, but the precise number depends on how you define and count them.