Meal Prep Portions Calculator
How much to cook for a week of meals — portions, total weight, container count and what it costs per meal against buying lunch.
Batch cooking is a multiplication problem with one trap: cooked and raw weights differ substantially.
How the meal prep portions calculator works
Batch cooking is a multiplication problem with one trap: cooked and raw weights differ substantially. Rice roughly triples, pasta doubles, and meat loses a quarter, so a recipe scaled on raw weight produces a very different amount of food than expected.
The comparison that motivates it is the cost per meal. Prepping at four a serve against buying at eighteen saves seventy a week, which is the number that makes the two hours on a Sunday worth it or not.
Formula: total = meals × portion; saving = (bought − prepped) × meals
Worked examples
| Inputs | Total cooked weight (kg) | Note |
|---|---|---|
| Ten meals at 400 g | 4 | 4 kg, saves 138 a week |
| Smaller portions | 3 | 3 kg |
| Cheaper alternative | 4 | a much smaller saving |
FAQFrequently asked questions
How much food is a portion?
Three hundred and fifty to 450 g for a main meal, depending on density and appetite. Weigh a meal you were happy with and use that.
Does cooked weight differ from raw?
Substantially. Rice roughly triples, pasta doubles and meat loses about a quarter. Scale recipes on the cooked figure.
How long does prepped food keep?
Three to four days refrigerated, three months frozen. Prepping ten meals usually means freezing half of them.
Is meal prep worth the time?
The saving-per-hour row answers it for your own numbers. At typical restaurant prices it is one of the better-paid hours in the week.
What containers should I use?
Something you can see into and stack. Seven hundred and fifty millilitres suits a single main; anything larger encourages over-portioning.
Where these figures come from
- US FDA — Safe Minimum Internal Temperatures — the internal temperatures the roasting calculator targets
- NIST SP 811 — Guide for the Use of the International System of Units — the exact weight and volume conversions used throughout
- UK Food Standards Agency — food safety and labelling standards
Last checked: September 2026. Baking ratios follow standard baker's percentage practice; roasting guidance follows published safe internal temperatures.