Grip Strength Calculator

Grip strength is how hard you can squeeze a hand dynamometer, a handheld device that reads force in kilograms or pounds. It is a quick, low-cost check of overall muscle strength. This calculator shows where your reading sits compared with other adults.

What Grip Strength Measures

Grip strength measures the peak force of the muscles in your hand and forearm. It does not measure muscle size, fitness or health on its own.

The Formula

There is no single equation. The calculator looks up the reference values for your age and sex, then places your reading among them. The main standard score is a z-score:

z = (your grip - average grip for your age and sex) / standard deviation for your age and sex

The reference values come from a pool of 12 British studies¹.

How This Calculator Computes Your Result

Enter your sex, age and up to three grip readings from either hand in kg or lb. The tool uses the highest one, as the reference study did. Pounds are converted to kilograms (1 lb = 0.45359237 kg). The reference table moves in steps of five years, so the tool blends the two nearest ages to match your exact age. It then shows your percentile band, the typical range for your group, your z-score, and two low-strength checks.

What Your Result Means

Your percentile tells you what share of people your age and sex have a weaker grip than you. The reference data give the 10th, 25th, 50th, 75th and 90th percentiles¹.

To give you a feel for the numbers, here are values from the same source (kg)¹:

The calculator also checks your best reading against two published cutoffs for low grip strength.

The EWGSOP2 cutoffs sit 2.5 standard deviations below the average of young adults in the same British data²; the SDOC cutoffs are higher and flag more people³. Both were written with older adults in mind. A reading under a cutoff is one sign researchers use when screening for low muscle strength. It is not a diagnosis.

How to Measure Correctly

A standard test uses these steps⁴:

- Sit upright with your back, hips and knees at about 90 degrees.

- Keep your upper arm against your side, elbow bent to 90 degrees, forearm in a neutral position (thumb up), wrist straight.

- Hold the device upright. Do not rest the arm on a table.

- Squeeze as hard as you can for about three seconds.

- Rest about a minute between attempts, and do up to three on each hand. Use your highest reading.

Use the same device each time you test. On a Jamar-style dynamometer, set the handle to the second position⁴.

Why the Type of Dynamometer Matters

The Jamar hydraulic dynamometer is the most used device in research and has well-established reliability⁵. Seven of the twelve studies behind the reference table used a Jamar. The others used Smedley, Nottingham electronic or Takei devices, and one study used a Harpenden device in its first round. The authors found results were fairly robust to device, with centiles usually differing by less than 10 percent¹. Even so, a cheap spring gauge or another digital model can read differently from a Jamar, so these norms fit best when your device is a good one.

Grip Strength and Long-Term Health

The strongest evidence comes from the PURE study. It followed 139,691 adults in 17 countries for a median of 4 years and measured grip with a Jamar⁶. For every 5 kg lower grip strength, the risk of death from any cause was 16 percent higher (hazard ratio 1.16). Heart-related death was 17 percent higher, heart attack 7 percent higher and stroke 9 percent higher⁶. The study reported that grip strength predicted all-cause and cardiovascular death better than systolic blood pressure⁶.

This is an association. It does not show that raising grip strength lowers risk.