This free protein calculator shows how many grams of protein you need each day, based on your age, weight, activity and goal. It is built for adults over 40, when protein needs quietly go up while appetite often goes down. You also get your target per meal and a simple guide to what that looks like on your plate.
How much protein do you need per day?
The official guideline for adults is 0.8 grams of protein per kilogram of body weight. That number was set to prevent deficiency, not to keep your muscles strong as you age. Expert groups that study older adults now recommend more: 1.0 to 1.2 g/kg for healthy people over 65, and up to 1.5 g/kg for those who are active or recovering from illness.
Protein needs by age and activity
| Who you are | Grams per kg per day | For a 75 kg (165 lb) person |
|---|---|---|
| Adult under 50, mostly sitting | 1.0 | 75 g |
| Adult 50 to 64, active | 1.3 | about 100 g |
| Adult 65+, active | 1.4 | about 105 g |
| Any age, strength training | 1.4 to 1.6 | 105 to 120 g |
| Losing fat or building muscle | 1.6 to 2.0 | 120 to 150 g |
A large review of 49 studies found that muscle gains from strength training level off at around 1.6 g/kg a day. Going higher is safe for healthy people but brings little extra benefit.
Why protein matters more after 40
From around 40, adults lose muscle every year if they do not use it, a process called sarcopenia. Older muscles also respond less to the same amount of protein, so you need a bit more to get the same effect. Muscle is not only about strength: it is your biggest store for blood sugar and helps keep your metabolic age low and your grip strength high.
How to split your protein across the day
- Aim for 25 to 40 g per meal. Older muscles need a bigger dose at one time to start building. Two small snacks do not do the same job as one proper protein meal.
- Fix breakfast first. Most people eat little protein in the morning and a lot at dinner. Eggs, Greek yogurt or cottage cheese make an easy start.
- Pair it with strength training. Protein works best when your muscles have a reason to use it. Start with our strength training guides.
- Use food first. Protein powder is convenient, but meat, fish, eggs, dairy, beans, lentils and tofu also bring vitamins and fibre.
Protein calculator FAQ
How much protein do I need after 50?
Most healthy adults over 50 do well with 1.0 to 1.2 g of protein per kg of body weight a day, and more if they train or are losing weight. For a 70 kg person, that is roughly 70 to 85 g a day.
Is too much protein bad for your kidneys?
For people with healthy kidneys, intakes up to about 2 g/kg a day are considered safe. If you have chronic kidney disease, your doctor may advise less, so ask before increasing your protein.
Should I use my current weight or my goal weight?
Use your current weight if you are near a healthy weight. If you carry a lot of extra weight, use your goal weight, or check your waist-to-height ratio first to see where you stand.
Can I get enough protein without meat?
Yes. Combine dairy, eggs, beans, lentils, tofu, tempeh and soy milk across the day. Plant proteins are slightly less effective per gram, so aim for the upper end of your range.
This calculator is for education, not diagnosis. It does not replace advice from your doctor or dietitian.
Sources
- Bauer J. et al. Evidence-based recommendations for optimal dietary protein intake in older people: a position paper from the PROT-AGE Study Group (JAMDA, 2013)
- Morton R.W. et al. A systematic review, meta-analysis and meta-regression of the effect of protein supplementation on resistance training-induced gains in muscle mass and strength (British Journal of Sports Medicine, 2018)
- Deutz N.E. et al. Protein intake and exercise for optimal muscle function with aging: recommendations from the ESPEN Expert Group (Clinical Nutrition, 2014)
