Estimate your daily protein target from body weight and activity level in your browser. A general estimate, not medical advice.
Protein Calculator Online
Estimate your daily protein target from body weight and activity level in your browser. A general estimate, not medical advice.
The Protein Calculator runs entirely in your browser and the weight and activity level you enter never leave your device. Results are a general estimate only, not medical advice.
Protein Calculator estimates how many grams of protein you should aim for each day based on your body weight and activity level. It applies standard grams-per-kilogram ranges used in sports nutrition — around 0.8 g/kg for a sedentary lifestyle, rising to 1.2–1.6 g/kg for people who train regularly, and 1.6–2.0 g/kg for athletes focused on building or preserving muscle. Enter your weight in kilograms or pounds, pick an activity level, and it instantly shows a low-to-high protein range in grams per day. It is useful for planning meals, checking a macro split, or sanity-checking a nutrition app's recommendation. This is a general estimate, not medical advice — talk to a doctor or registered dietitian about your specific needs, especially with any kidney condition. Everything runs locally in your browser.
Features
Estimates a daily protein range in grams from weight and activity level
Switches between metric (kg) and US (lb) units with one click
Uses standard g/kg ranges for sedentary, active, and athlete activity levels
Shows both the low and high end of the recommended range
Copy button for a plain-text summary of weight, activity, and protein range
Clear error message when the weight field is missing or invalid
Notes clearly that results are general estimates, not medical advice
Runs entirely in your browser with no health figures sent anywhere
How to use the Protein Calculator
Enter your body weight and choose kg or lb
Pick your activity level: sedentary, active, or athlete
Read the recommended daily protein range in grams
Copy the summary if you want to save or share it
Example
Input
70 kg, athlete
Output
Protein: 112–154 g/day
Common errors & troubleshooting
The weight was entered in pounds while the unit toggle was still set to kg, giving an unrealistically high protein range. — Switch the unit toggle to lb before typing a pounds figure, or convert to kilograms first.
The activity level was left on the default and the range looks too low for a heavy training schedule. — Select Athlete for intense, frequent training aimed at building or preserving muscle — Active is meant for a few regular workouts a week.
The protein range shows 0 g/day even though a weight was typed. — Check for stray letters or a negative sign in the weight field — the Protein Calculator needs a plain number greater than 0.
Frequently asked questions
What formula does the Protein Calculator use?
It multiplies your body weight in kilograms by a grams-per-kilogram range that depends on activity level: roughly 0.8 g/kg for sedentary, 1.2–1.6 g/kg for active, and 1.6–2.0 g/kg for athlete, giving a low and high figure in grams per day.
Can the Protein Calculator use pounds instead of kilograms?
Yes. Use the kg / lb toggle next to the weight field — the calculator converts pounds to kilograms internally before applying the formula.
Is the Protein Calculator's result medical advice?
No. It provides a general estimate only, based on standard sports-nutrition ranges, and is not medical advice. Talk to a doctor or registered dietitian about your specific needs, especially if you have a kidney condition.
Why does the Protein Calculator give a range instead of one number?
Protein needs vary with training intensity, goals, and individual factors, so the calculator shows a low-to-high range rather than a single overly precise figure.
How is Active different from Athlete in the Protein Calculator?
Active covers regular workouts a few times a week, while Athlete covers intense training most days aimed at building or preserving muscle, which pushes the recommended g/kg range higher.
Does the Protein Calculator upload my weight anywhere?
No. The Protein Calculator runs entirely in your browser. The weight and activity level you enter never leave your device.
Related tools
Macro Calculator — Split your daily calories into protein, carbs and fat grams by ratio.
Calorie Calculator — Estimate daily calories to maintain, lose or gain weight from your stats.
Carbohydrate Calculator — Estimate daily carbohydrate grams from your calories and diet split.
Fat Intake Calculator — Estimate daily dietary fat grams from your calories and target percentage.
TDEE Calculator — Estimate total daily energy expenditure from BMR and activity level.