Protein Calculator Guide: Formula & Worked Example
Short answer
Daily protein needs by activity and goal. In the fixed example below, protein per day is 112 g. Your answer depends on the inputs and assumptions you choose.
Formula
Result = Protein Calculator calculation using weight, goal / activity
The inputs are weight, goal / activity. Use the input scale shown beside each field and keep time periods and units consistent. Only round the final result for display.
Worked example
- Weight
- 70
- Goal / activity
- 1.6
- Protein per day: 112 g
- Per meal (4 meals): 28 g
- Calories from protein: 448 kcal
Understanding the result
Daily protein needs by activity and goal. Start with the base example, then replace each value with the figure that matches your situation.
Weight
The example uses 70 kg for weight. This is an illustration, not a recommended value. Keep the unit and time period shown by the field.
Goal / activity
The example uses Build muscle for goal / activity. This is an illustration, not a recommended value. Keep the unit and time period shown by the field.
What the comparison means
The comparison changes only weight, keeping every other example input fixed. This isolates that input's effect on the primary result. It does not predict future outcomes.
This is a screening or planning estimate, not a diagnosis. Age, pregnancy, medication and individual medical history can change how the result should be interpreted.
Comparison
| Scenario | Input | Result |
|---|---|---|
| Lower input | Weight: 56 kg | Protein per day: 90 g |
| Base example | Weight: 70 kg | Protein per day: 112 g |
| Higher input | Weight: 84 kg | Protein per day: 134 g |
Common mistakes
- Using the wrong units for weight.
- Comparing results while changing more than one input at a time.
- This is a screening or planning estimate, not a diagnosis. Age, pregnancy, medication and individual medical history can change how the result should be interpreted.
Checklist
- Confirm weight is expressed in kg.
- Confirm goal / activity.
- Check the result against your source or provider.
Calculators Percentage Editorial Team
Calculator guides from the Calculators Percentage team. These introductory examples are educational, not professional advice.
Last reviewed:
This is a screening or planning estimate, not a diagnosis. Age, pregnancy, medication and individual medical history can change how the result should be interpreted.