Meal Prep Calculator
Plan your meal prep with calculated portions, macro distribution, and grocery shopping estimates.
Important Health Disclaimer
This calculator provides general health information based on standard medical formulas and WHO guidelines. Results are for informational and educational purposes only and should not be considered as professional medical advice or a personal care recommendation.
For health concerns, medical conditions, fitness plans, or dietary decisions, please consult with qualified healthcare professionals, licensed physicians, registered dietitians, or certified fitness trainers who can evaluate your individual health status and medical history.
Individual health needs vary significantly. These calculations are general estimates and may not be appropriate for everyone, especially those with existing medical conditions, pregnant women, children, or elderly individuals.
Not a substitute for qualified professional guidance
Meal Prep Settings
Typically 3-5 days for freshness
Total Meals to Prep
20
500 calories each
Per Meal Macros
Protein
38g
Carbs
50g
Fat
17g
Estimated Grocery List
- Protein (chicken/meat/tofu)3.0 kg
- Carbs (rice/pasta/grains)4.0 kg
- Vegetables4.0 kg
- Cooking time estimate2.5 hrs
Meal Prep Tips
Storage
- - Use airtight containers
- - Label with date and contents
- - Store in fridge for 3-4 days
- - Freeze for longer storage (5+ days)
Cooking
- - Batch cook proteins first
- - Use one-pan meals for efficiency
- - Season proteins differently for variety
- - Undercook veggies slightly for reheating
Organization
- - Plan your menu before shopping
- - Prep ingredients first, then cook
- - Set aside 2-3 hours for prep
- - Clean as you go
What Is the Meal Prep Calculator?
Meal Prep Calculator helps estimate how many meals to prepare, how many calories and macros each meal contains, and how much basic grocery quantity may be needed for a prep period.
The calculator uses the daily calorie target, meals per day, number of prep days, number of people, and macro percentages entered on the page. It then splits the totals into per-meal protein, carbohydrate, and fat targets.
Use the output as a planning estimate for shopping and portioning. It does not account for allergies, medical dietary needs, exact recipes, cooking loss, food brands, or personal nutrition advice.
Meal Prep Calculation Method
The calculator first converts the macro percentages into grams per day. Protein and carbohydrates use 4 calories per gram, while fat uses 9 calories per gram. Those daily macro grams are divided by the selected meals per day to estimate per-meal portions.
Total meals are calculated from meals per day, prep days, and people. Grocery estimates are broad planning values: protein foods are estimated from about 25 g protein per 100 g of food, carbohydrate foods from about 25 g carbohydrate per 100 g of cooked grains, and vegetables from about 200 g per meal.
Core Meal Prep Logic
Where:
- Daily calories= The calorie target entered for one person for one day
- Meals per day= How many meals the daily calories are split into
- Prep days= How many days of meals are being prepared
- People= How many people the meal prep covers
- Macro percentages= Protein, carbohydrate, and fat shares of the daily calorie target
Understanding the Results
The main result shows the total number of meals to prepare and the estimated calories in each meal. The macro cards show protein, carbohydrates, and fat per meal, rounded to whole grams for easier portion planning.
| Result | What It Means | Planning Use |
|---|---|---|
| Total meals | Meals per day multiplied by prep days and people. | Use it to choose containers and batch size. |
| Per-meal macros | Daily macro grams divided by meals per day. | Use it as a target when portioning meals. |
| Grocery estimates | Approximate protein foods, carbohydrate foods, and vegetables for the full prep period. | Use it as a shopping starting point, then adjust for recipes and preferences. |
How to Use This Calculator
- Enter daily calories: Use the calorie target you want each person to follow for one day.
- Choose meals per day: This controls how calories and macros are divided across meals.
- Set prep days and people: These values scale the total meal count, grocery estimates, and container count.
- Select or adjust macros: Balanced, high-protein, and low-carb presets update the macro percentages. Custom values can be entered manually.
- Check the totals: If protein, carbohydrate, and fat percentages do not add to 100%, adjust them before using the results for planning.
Assumptions and Limits
Results are rounded for practical meal prep. Per-meal calories are shown as whole calories, per-meal macros as whole grams, grocery quantities to one decimal place in kilograms, and cooking time to one decimal place in hours.
The grocery list is intentionally approximate. Actual food weight depends on the ingredient, cooked versus raw weight, water content, trim loss, recipes, sauces, and serving preferences.
This tool is for general planning only. It does not account for medical dietary requirements, allergies, pregnancy, diabetes, kidney disease, eating disorders, medication interactions, or therapeutic diets. If you have medical dietary needs, consult a qualified healthcare professional or registered dietitian.
Worked Examples
Five-day meal prep for one person
Problem:
A user plans 2,000 calories per day, 4 meals per day, 5 prep days, and 1 person.
Solution Steps:
- 1Step 1: Total meals = 4 meals per day x 5 days x 1 person.
- 2Step 2: Calories per meal = 2,000 / 4.
- 3Step 3: Macro grams are calculated from the selected percentages and divided across 4 meals.
- 4Step 4: Grocery quantities scale to the full 20-meal prep period.
Result:
The calculator estimates 20 meals, about 500 calories per meal, per-meal macro targets, and approximate grocery quantities.
Scaling for two people
Problem:
A user keeps the same daily calorie target and macro percentages but changes people from 1 to 2.
Solution Steps:
- 1Step 1: Per-meal calories and per-meal macros stay the same for each person.
- 2Step 2: Total meals double because the prep covers two people.
- 3Step 3: Grocery quantities and containers also double.
Result:
The calculator helps scale shopping and containers without changing the per-person meal target.
Changing the macro preset
Problem:
A user switches from balanced to high protein before planning meals.
Solution Steps:
- 1Step 1: The high-protein preset increases protein percentage and adjusts carbs and fat.
- 2Step 2: Protein grams per meal rise while the other macro targets change.
- 3Step 3: The estimated protein-food quantity changes with the higher protein target.
Result:
The result shows how macro choices affect portions and grocery planning.
Tips & Best Practices
- ✓Keep macro percentages at 100% total before using the results.
- ✓Adjust grocery quantities for the exact recipes and ingredients you plan to cook.
- ✓Use cooked-weight assumptions consistently when comparing portions.
- ✓Plan shorter prep windows for foods that do not store well.
- ✓Label containers with the date and contents.
- ✓Consult a qualified professional for medical dietary requirements.
Frequently Asked Questions
Sources & References
- USDA FoodData Central (2026)
- Dietary Guidelines for Americans (2026)
Last updated: 2026-07-16
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Related Calculators
Sources
- •World Health Organization (WHO) — Global health metrics, disease classification, and nutritional standards. who.int
- •Centers for Disease Control and Prevention (CDC) — Health statistics, BMI guidelines, and disease prevention data. cdc.gov
- •National Institutes of Health (NIH) — Medical research, clinical guidelines, and health calculators. nih.gov
- •Mayo Clinic — Clinical health information, disease reference, and wellness guidance. mayoclinic.org
For a complete list of all references used across the site, visit our full sources page.
Editorial Note
MyCalcBuddy Editorial Team
This page is maintained as an educational calculator reference.
Formula Source: WHO Health Metrics Standards
by World Health Organization