6 Minute Walk Test Calculator

The six-minute walk test (6MWT) measures how far you can walk on a flat course in six minutes. Healthy people of different ages and sizes walk different distances, so this calculator turns your distance into a percent of the predicted value and checks it against a lower limit of normal.

What the 6 Minute Walk Test Measures

The 6MWT is a self-paced test of everyday, below-maximum exercise capacity. It reflects how the heart, lungs, circulation and muscles work together during exercise². Its main use is to measure response to treatment in heart or lung disease, and a low distance alone is "nonspecific and nondiagnostic"².

The Formula

Men: predicted distance (m) = 7.57 x height (cm) - 5.02 x age - 1.76 x weight (kg) - 309

Women: predicted distance (m) = 2.11 x height (cm) - 2.29 x weight (kg) - 5.78 x age + 667

Percent of predicted = your distance / predicted distance x 100

Lower limit of normal = predicted distance - 153 m (men) or - 139 m (women)

These reference equations come from a 1998 study of 117 healthy men and 173 healthy women aged 40 to 80¹.

How This Calculator Computes Your Result

Enter your distance in meters or feet, plus your sex, age, height and weight in metric or imperial units. Imperial values are converted to metric first (1 ft = 0.3048 m, 1 in = 2.54 cm, 1 lb = 0.45359237 kg). You see your predicted distance and lower limit of normal to the nearest whole meter or foot, your percent of predicted, and your average walking speed. Ages 18 to 90 are accepted, with a note outside the study's 40 to 80 range.

What Your Result Means

Your result gets one of two labels, based on the lower limit of normal (LLN) published with the equations¹:

Percent of predicted has no official cutoff for good or poor, so the LLN is the better yardstick. For example, a 72-year-old man (170 cm, 95 kg) who walks 310 m reaches only 69% of predicted but is still above his LLN of 296 m. A 50-year-old woman (160 cm, 70 kg) who walks 380 m reaches 68% of predicted but is below her LLN of 416 m.

Predicted distances and LLNs for two example body sizes¹:

How to Measure Correctly

The equations fit only a test done the standard way, as set out by the American Thoracic Society (ATS)²:

• The course is indoors, flat, straight and 30 m (about 100 ft) long, with a cone at each turnaround point. A shorter course with more turns lowers the distance.

• Wear comfortable clothes and walking shoes, use your usual walking aid, and keep taking your usual medicines.

• Do not exercise hard in the 2 hours before the test, and sit at rest near the start for at least 10 minutes first.

• The goal is to walk as far as possible in 6 minutes, not to jog or run. You may slow down, stop and rest, then carry on.

• The tester uses only short, standard phrases of encouragement each minute, and does not walk with you.

• A treadmill is not recommended for this test.

The ATS guideline lists reasons to stop the test at once: chest pain, breathlessness you cannot tolerate, leg cramps, staggering, heavy sweating, or a pale or ashen look². It also describes the 6MWT as a supervised test, done where a fast emergency response is possible².

What Counts as a Meaningful Change

In adults with chronic lung disease, the ERS/ATS technical standard puts the smallest change that matters to patients at about 30 m, likely between 25 and 33 m³. The older ATS guideline cited a mean of 54 m in people with COPD, and said an individual improvement of more than 70 m is needed to be 95% sure of a real change². Practice matters too: on a second test a day later, average distance rose by 0 to 17%², so the ERS/ATS standard advises two tests, keeping the best, when tracking change³.

Why Your Result Can Differ From the Prediction

Age, height, weight and sex explained only about 40% of the differences in distance between healthy people in the study¹. Effort, a previous test and course length also shift the result². In a 2022 Italian study of 530 healthy adults, the Enright and Sherrill equations overestimated distance by 13 m in men and underestimated it by 6 m in women over 40⁴. The ERS/ATS standard advises using local reference equations where possible³.