What this calculator does
This tool estimates how many calories (kcal) you burn doing carpentry, home repair, remodeling, or general construction work. It uses the MET (metabolic equivalent) method, a universal physiology approach in which each activity is assigned a MET value representing its energy cost relative to sitting quietly. The MET values listed here are drawn from a revised "Physical Activity METs" table (a localized adaptation of the international Compendium of Physical Activities), but the formula itself applies everywhere.
How to use it
Pick the activity that best matches your task from the dropdown — its MET value is built in. Enter how long you worked in minutes and your body weight in kilograms, then read off the estimated calories burned and the exercise intensity in METs.
The formula explained
The calculation is: $$\text{calories} = \text{MET} \times \text{weight(kg)} \times \text{time(hours)} \times 1.05$$. One MET roughly equals 1.05 kcal per kilogram of body weight per hour, so multiplying these factors gives total energy expenditure. Duration is entered in minutes and converted to hours by dividing by 60. Some sources use a factor of 1.0; this tool fixes it at 1.05 in line with common Japanese health guidance.
Worked example
Suppose you do general workshop home repair (3.0 MET) for 90 minutes at 65 kg. Time in hours = \(90 / 60 = 1.5\). $$\text{Calories} = 3.0 \times 65 \times 1.5 \times 1.05 = 307.13 \text{ kcal}$$ and the exercise intensity is 3.0 METs.
FAQ
Are the results exact? No. MET values are population averages; your real burn varies with fitness, technique, and effort. Treat the number as an estimate, not medical advice.
Why does heavy sawing burn more? Strenuous tasks have higher MET values (up to 6–7), reflecting greater oxygen and energy demand than light finishing work.
Do I subtract resting calories? This gives gross energy expenditure for the activity. To get the net "extra" burn you could subtract roughly one MET-hour, but most calorie tools report the gross figure shown here.
