Protein Calculator
Find out how much protein you need per day to hit your goals
This protein calculator returns your daily protein target in grams, based on your bodyweight, your goal (fat loss, maintenance, muscle gain), and your activity level. It also breaks the daily total into per-meal targets at 3, 4, or 5 meals, and shows what that looks like in real food (eggs, chicken, whey, Greek yogurt, salmon).
The math uses g/kg multipliers grounded in the International Society of Sports Nutrition position stand (Jager et al., 2017), which recommends 1.4 to 2.0 g/kg for exercising individuals, with the higher end (2.3 to 3.1 g/kg) appropriate during fat loss to protect lean mass.
Built and reviewed by Kazi Habib, B.Pharm, MBA, PMP. The deep dive below covers why the calculator returns a different number than the standard 0.8 g/kg RDA (the RDA is a minimum to avoid deficiency, not an optimum for body composition), why distribution across meals matters more than people think, and what to do if the daily total feels impossible to hit through food alone (it usually means a single whey scoop, which is the cheapest 25g of protein on the market).
How this calculator works
We multiply your bodyweight in kg by a g/kg multiplier that depends on goal and activity. The multipliers sit inside the evidence-based ranges: fat loss with training at 2.0 to 2.4 g/kg (higher end for aggressive cuts, protects lean mass), maintenance with training at 1.6 to 2.0 g/kg, muscle gain at 1.6 to 2.2 g/kg, and sedentary at 1.2 to 1.4 g/kg.
The per-meal breakdown divides your daily total across 3, 4, or 5 meals so you can see realistic per-sitting targets. The food equivalency builds an example day using common protein sources at standard serving sizes.
When to use this calculator
Use this when you are starting a new program and need a target instead of guessing, when you are running a fat loss phase and want to make sure protein stays high enough to protect muscle, when you are over 65 and tracking protein to defend against sarcopenia, or when you want to know whether 1 whey scoop per day is enough or whether you need 2 (it depends on your bodyweight and what your meals look like).
When NOT to use this calculator
Skip the high-protein recommendations if you have chronic kidney disease (eGFR under 60 mL/min). High protein is contraindicated; talk to a renal dietitian. If you are pregnant or breastfeeding, the RDA differs and you need a prenatal RD. If you are an elite athlete in a weight-cutting sport, the numbers here are floor recommendations; sport-specific cutting protocols go higher.
What the result actually means
The result is a daily target. Your body absorbs and uses roughly 25 to 40g of protein per meal for muscle protein synthesis purposes (Lonnie et al., 2018, Nutrients summarises the meal-distribution evidence). Anything beyond that per meal still gets used for energy or other nitrogen needs, but the muscle-building signal saturates around 0.4 g/kg/meal for trained adults.
That is why the per-meal breakdown exists. If your daily target is 180g, you do not need a 180g dinner; you need 4 meals of 45g each, which is much more realistic. A 45g meal looks like 150g of grilled chicken plus a Greek yogurt, or one whey scoop plus 4 eggs.
The Morton 2018 BJSM meta-analysis of 49 trials and 1,863 participants found additional muscle gains plateau around 1.6 g/kg/day for resistance-trained adults. If your calculator returned 2.2 g/kg, that is a safety margin for body recomp, not a strict requirement. You will not lose gains at 1.7 g/kg if life forces a low day.
Pharmacist take
Protein powder labels are the most reliably dishonest category in supplements. Independent lab testing across multiple cycles has documented brands shorting their label claim by 16 to 28%. ConsumerLab and Labdoor both publish protein-content verification reports periodically. The third-party-tested brands I trust for label accuracy: NSF Certified for Sport whey (Klean Athlete, Thorne), Informed Sport tested whey (Optimum Nutrition Gold Standard verified batches), and Naked Whey (no certification but published COA). Anything advertising amino spiking proof without a current COA is marketing.
Halal, Canadian, and dietary considerations
For Canadian readers, the cheapest reliable protein sources per gram remain: Costco rotisserie chicken (about $0.013 per gram of protein), eggs from Bulk Barn or Walmart (about $0.025 per gram), Greek yogurt at Costco (Two Good or Oikos Pro), and whey isolate via iHerb Canada (about $0.04 per gram). Halal-certified meat is widely available at H&W, Adonis, and most ethnic grocers in major Canadian cities.
Methodology and sources
The g/kg multipliers reflect the ISSN position stand (Jager 2017), the Morton 2018 meta-analysis, and the per-meal distribution research summarised in Lonnie 2018. The RDA of 0.8 g/kg is the minimum to prevent deficiency in sedentary healthy adults, established by the Institute of Medicine and adopted by Health Canada in its DRI tables. The training population needs 2 to 3x that minimum, which is what this calculator returns.
Why Your Protein Target Matters More Than You Think
Protein is the one macronutrient where 'enough' for general health is substantially different from 'optimal' for body composition, strength, and aging well. The U.S. RDA of 0.8g/kg is designed to prevent deficiency, not optimize performance — and it hasn't been updated in decades despite overwhelming newer evidence.
For adults who exercise, the International Society of Sports Nutrition (Jäger et al., 2017) recommends 1.4–2.0g per kg of bodyweight daily. That's nearly double the RDA. For older adults (50+), research supports even higher intakes — 1.2–1.6g/kg — to counter age-related muscle loss (sarcopenia). And during fat loss, going as high as 2.2–2.4g/kg helps preserve every bit of hard-earned muscle while you're in a caloric deficit.
Quality matters alongside quantity. Complete proteins (containing all 9 essential amino acids) include whey, casein, egg, meat, fish, soy, and quinoa. Plant proteins like rice, pea, and hemp are complete when combined. Leucine content is especially important — this amino acid triggers muscle protein synthesis (MPS). Aim for 2.5-3g of leucine per meal, which is roughly 25-30g of high-quality protein. This 'leucine threshold' is why spreading protein across 3-5 meals works better than loading it into one meal.
Timing matters less than people think — but it's not irrelevant. Eating protein within 2 hours of training optimizes recovery. Pre-sleep protein (30-40g casein) reduces overnight muscle breakdown. For most people, the daily total is what drives results. If you're consistently hitting your target, when you eat it is a secondary optimization.
Keep learning
- →How Much Protein Do You Need? (Full Guide)Complete breakdown by goal, age, and activity level.
- →Whey vs Plant Protein: Which Is Better?Head-to-head on absorption, MPS, and practical considerations.
- →Compare Protein PowdersSide-by-side of Optimum Nutrition, Ghost, Dymatize, Transparent Labs.
- →Halal Protein Powders (Canada)Certified halal options for Muslim athletes.
Protein Calculator FAQ
It depends on your goal and activity. The general recommendation for active adults is 1.6-2.2 grams per kg of body weight. For sedentary adults, 0.8 g/kg is the minimum. If you are trying to lose fat while preserving muscle, aim for the higher end (2.0-2.2 g/kg).
For healthy individuals, protein intakes up to 3.0 g/kg have been studied without adverse effects on kidney function. However, eating excessive protein leaves less room for carbs and fats which are also important. A balanced approach within 1.6-2.2 g/kg covers most peoples needs effectively.
Plant proteins can be equally effective when you eat a variety of sources (legumes, tofu, tempeh, grains, seeds) to get a complete amino acid profile. Some plant proteins are lower in leucine, which is important for muscle protein synthesis — combining sources or slightly increasing total intake compensates for this.
Total daily protein intake matters more than timing. That said, spreading protein across 3-5 meals (20-40g each) optimizes muscle protein synthesis throughout the day. A protein-rich meal within 2-3 hours of training is beneficial but the 'anabolic window' is much wider than previously thought.