Quick Answer: There is no single strongest muscle in the human body, because the answer depends on how you measure strength. The masseter (jaw muscle) produces the most force relative to its size, the gluteus maximus generates the most raw force overall, and the heart does the most total work over a lifetime without ever resting.
The Strongest Muscle in the Human Body by Category
| Category | Muscle | Why It Wins |
|---|---|---|
| Force relative to size | Masseter (jaw) | Bite force up to roughly 890 N from a small muscle |
| Largest raw force | Gluteus maximus | Moves the whole body’s weight during hip extension |
| Most total work over time | Heart | Beats roughly 100,000 times a day without rest |
| Most fatigue-resistant | Soleus (calf) | Holds posture upright for hours at a time |
Each of these muscles is “strongest” only within its own definition of strength. Keep reading for what each one actually does, and why the popular claim about the tongue doesn’t hold up.
The Masseter: Strongest by Force Relative to Size
The masseter sits along the jaw and is the main muscle used for biting and chewing. Studies measuring bite force at the molars put the average adult in the range of 400 to 550 newtons, with some individuals exceeding that. For a muscle small enough to cover with two fingers, that output relative to its size is unmatched by any other skeletal muscle, which is why reference sources commonly name it the strongest “pound for pound.” Like every skeletal muscle, the masseter works by pulling on bone — in this case the mandible, one of the 206 bones that make up the adult skeleton.
The Gluteus Maximus: Strongest by Raw Force
If the question is which muscle can move the largest total load, the gluteus maximus takes the title. As the largest muscle in the body, it drives hip extension during running, climbing stairs, and standing up from a squat, generating forces that dwarf a smaller muscle like the masseter once you account for moving your entire body weight rather than clamping down on an object. Building this muscle is a common focus of lower-body training programs, alongside supporting muscle groups covered in guides like workout machines for biceps for the upper body equivalent.
The Heart: Hardest Working Muscle
The heart is cardiac muscle, a different tissue type from the skeletal muscles above, and it wins on a completely different measure: total lifetime output. It pumps roughly 2 ounces of blood with every beat, adds up to thousands of gallons a day, and can beat over 3 billion times across a lifetime without ever stopping to rest. No skeletal muscle could sustain that kind of continuous, uninterrupted work. Because it never gets a rest day the way skeletal muscle does, keeping it in good condition matters — see our guide on how to make your heart strong for practical steps.
The Quadriceps and Soleus: Other Contenders
The quadriceps femoris, the muscle group at the front of the thigh, is sometimes cited alongside the glutes for raw force, since it’s responsible for extending the knee during running, jumping, and lifting. The soleus, a deep calf muscle, works almost continuously to keep the body upright against gravity while standing, making it one of the most fatigue-resistant muscles in the body even though it isn’t the most powerful in a single burst. These two are easy to overlook when people ask what is the strongest muscle in the human body, since neither wins a single category outright, but building either one relies on the same basics as any strength goal: progressive training paired with enough protein, covered in our guide to protein powder for weight gain.
Debunking the Tongue Myth
The tongue is often repeated as the strongest muscle in the body, but that claim doesn’t hold up under any of the definitions above. It’s genuinely remarkable for its range of movement and endurance, being made of eight interwoven muscles that work together for speech, chewing, and swallowing, but it does not lead in bite force, raw strength, or lifetime workload.
Frequently Asked Questions
There isn’t one single answer. The masseter (jaw) is strongest relative to its size, the gluteus maximus produces the most raw force, and the heart does the most total work over a lifetime.
No. The tongue is unusually flexible and tireless, but it does not lead in bite force, raw strength, or total workload compared to the masseter, glutes, or heart.
The average adult can bite with roughly 400 to 550 newtons of force at the molars, produced mainly by the masseter muscle.
The heart is made of cardiac muscle, a distinct muscle type from the skeletal muscles that move your limbs, but it is still muscle tissue and is often included in strength comparisons for its lifetime workload.
The gluteus maximus, located in the buttocks, is the largest muscle by size and also produces the most raw force of any skeletal muscle.
Final Answer: The Strongest Muscle in the Human Body
There is no single strongest muscle — the answer depends on the measure. The masseter wins for force relative to size, the gluteus maximus for raw force, and the heart for total lifetime work. The popular claim that the tongue is the strongest muscle doesn’t hold up against any of these definitions, even though it is remarkably flexible and tireless in its own right.