Emergency food planning is easier when you stop thinking in random tins and start thinking in person-days.
A person-day means enough food for one person for one day.
For example, if you are storing food for 2 people for 7 days, that is 14 person-days of food. If you are storing food for a family of 4 for 30 days, that is 120 person-days.
At PrepareHQ, we recommend starting with a realistic amount of food you can store properly, then building up over time.
Why emergency food planning matters
Most people do not realise how quickly normal food supplies can become limited during disruption. Power cuts, delivery delays, extreme weather, household emergencies and local shortages can all make food planning more important.
You do not need to panic-buy. The better approach is to build a simple backup food supply that fits your household size, budget and storage space.
How to calculate food by person-days
Use this simple formula:
Number of people × number of days = person-days of food needed
Examples:
1 person × 3 days = 3 person-days
2 people × 30 days = 60 person-days
4 people × 90 days = 360 person-days
This helps you compare short-term emergency packs with larger food supplies.
3 days vs 1 month vs 3 months
A 3 day emergency food pack is a good starting point if you want basic backup food for short disruptions, power cuts or temporary supply issues.
A 1 month emergency food supply is better if you want more peace of mind and enough food to cover a longer disruption.
A 3 month emergency food supply is for people who want a more serious home preparedness setup without going straight into very large long-term storage.
How much food for a family of 4?
For a family of 4, the numbers increase quickly.
A 3 day supply is:
4 people × 3 days = 12 person-days
A 1 month supply is roughly:
4 people × 30 days = 120 person-days
A 3 month supply is roughly:
4 people × 90 days = 360 person-days
This is why family emergency food storage is usually easier when bought as a planned supply instead of random individual items.
Use our emergency food calculator
To make this easier, use the PrepareHQ emergency food calculator. Enter your household size and how many days you want to prepare for, then use the result to choose the right pack size.
Recommended starting options
If you are just starting, begin with a smaller pack so you can test the meals and understand what storage space you need.
Good starting points include:
3 day emergency food pack
5 day emergency food pack
1 month emergency food supply
Family emergency food supplies
FAQ
How much emergency food should I store?
A good starting point is 3 days of emergency food per person. After that, many households build toward 1 month, 3 months or longer depending on budget and storage space.
Is freeze-dried food better than supermarket food?
Freeze-dried food is useful because it has a long shelf life, is lightweight and is easy to store. Supermarket food can still be useful, but it usually needs more rotation.
Should I buy a large food supply straight away?
Not always. If you are new to emergency food, it is sensible to start with a smaller pack first, then build up once you know what you like and what you can store.