How to use this calculator
Start by entering the number of adults in your household. Toggle on children and pets if applicable. Then select how many days of supplies you want to prepare for. FEMA recommends a minimum of 3 days, but 7 to 14 days is a safer target for hurricanes, winter storms, and earthquakes.
Choose a scenario type to get targeted recommendations. Hurricane mode adds supplies like tarps, waterproof storage, and mosquito repellent. Wildfire mode emphasizes N95 masks and go-bag readiness. Winter storm mode adds backup heating, pipe insulation, and carbon monoxide detectors. The general setting covers any type of emergency.
The calculator outputs exact quantities for every essential supply category, an estimated cost for each item, and a total cost for your complete kit. Use it as a shopping list to build your kit over time.
Why most families are underprepared
According to FEMA, only 48% of Americans have emergency supplies, and just 39% have developed an emergency plan. The most common reason is not cost or effort. It is not knowing where to start. Generic checklists say "store water and food" without telling you how much your specific household actually needs.
The difference between a family of two and a family of five preparing for seven days is enormous. Two adults need 14 gallons of water. A family of five needs 35 gallons. That specificity is what this calculator provides, and it is what turns vague intentions into an actual supply list you can act on.
How to store emergency supplies properly
Where you store your kit matters as much as what is in it. Choose a cool, dry, dark location that every household member can access. A hallway closet, basement shelf, or garage cabinet all work. Avoid attics (extreme heat degrades food and batteries) and anywhere prone to flooding.
Keep a smaller go-bag near your front door or in your car with 72 hours of essentials in case you need to evacuate quickly. Your main supply kit stays at home for shelter-in-place situations. Having both covers the two most common emergency scenarios.
If you have an emergency fund for financial emergencies, think of your supply kit as the physical version of the same idea. Both exist so that when something goes wrong, you have already handled it.
Building your kit on a budget
A fully stocked 7-day kit for a family of four can cost $400 to $800 if you buy everything at once. But there is no reason to do that. The most practical approach is to add a few items each week during your regular shopping trip. Week one: buy extra water. Week two: grab canned goods. Week three: batteries and a flashlight. Within a month or two you have a solid kit without any single trip hurting your budget.
Dollar stores carry surprisingly good emergency basics including flashlights, batteries, first aid supplies, candles, and lighters. A NOAA weather radio ($20 to $30 online) and a decent power bank ($15 to $25) are the two items worth spending a little more on since they are critical when the power goes out. Our bulk buying calculator can help you figure out if buying canned goods in bulk saves you money compared to individual purchases.