Field Tool — Deep Pantry Calculator
PrepRation — Know exactly how much food your household needs — and what you're missing.
Work out the calories and macros your household needs for any duration, then tally your pantry stores to see how many days of food you really have. The deep pantry, made measurable.
01 — Requirements
What you need
Enter your household size and the duration you want to build stores for. The tool calculates total calories and breaks them down into protein, carbohydrate, fats and fibre.
2,500 kcal is a common adult average; raise for active adults, lower for children.
Macro split (% of calories)
Split totals 100%.
Standard survival split (~50% carbs, 20% protein, 30% fat) + fibre goal
Requirement summary
Total calories
kcal over 28 days
People × days
person-days of food
Based on 2,500 kcal/person/day · Fibre at 30g/person/day (NHS guideline). Figures are estimates for planning, not medical advice.
02 — Pantry Audit
What you have
Add the foods in your store, with the weight in grams. The tool tallies the calories and macros your pantry actually covers, then compares it against your requirement above.
Ticked foods are added to your pantry at 1,000g — adjust the grams in the table below.
| Food | Grams | Kcal | |
|---|---|---|---|
| White rice (dry) | 18,250 | ||
| Baked beans (tinned) | 1,740 | ||
| Tinned tuna | 1,740 | ||
| Total | 8,500g | 21,730 |
Coverage vs requirement
Pantry covers
days of food for 2 people
Bars fill as your pantry meets each target. A full bar means that macro is fully covered for the duration you set above.
03 — Water Planner
Water to cook & rehydrate
Dry stores need water to cook and rehydrate. This adds the cooking water your pantry demands on top of the drinking water your household needs across the whole period.
2 L is the NHS minimum for drinking & hygiene; raise for hot weather or exertion.
Where the cooking water goes
- 10,000 ml
Water summary
Drinking
Cooking
Total water needed
over 28 days for 2 people
Cooking water is estimated per 100g of dry stores (rice, pasta, oats, lentils, powdered milk, etc.). Store at least this much, plus a buffer for hygiene.
04 — Shopping List
Fill the gaps
Each nutrient your pantry falls short on is turned into a ready-to-buy staple, sized to reach full coverage. Print it, take it to the shop, and close the gap.
Recommended buys
| Food | Fills | Buy (g) | Kcal added |
|---|---|---|---|
| Lentils (dry) | Protein gap | 24,640g | 86,979 |
| White rice (dry) | Carbohydrate gap | 16,525g | 60,316 |
| Cooking oil | Fat gap | 4,612g | 40,767 |
| Rolled oats | Fibre gap | 15,150g | 58,934 |
| Total added | 60,927g | 246,996 |
Recommendations use dense UK staples (lentils, rice, oil, oats). Grams are rounded estimates — buy in whole packs and rotate what you store.
05 — Report Export
Keep it offline
Download your full plan — requirements, pantry, water, coverage and shopping list — as a CSV for spreadsheets or a clean PDF to print and keep in your grab file.
06 — Your Plans
Save your pantry
Create a free account to save your calculator plans — requirements, pantry, water and custom foods — and reload them next time you audit your stores.
Sign up free to store unlimited pantry calculations and reload them on any device.
Store what you eat. Rotate what you store.
A working pantry, not a bunker of freeze-dried regret. Read the field notes and keep your stores turning over.
Read the Food field notes