Every good preparedness plan starts with a number — how much food, how much water, how big a battery. Guessing at those numbers is the most expensive mistake in this hobby: oversize and you waste money, undersize and the plan fails on the one night it matters. These are the free calculators we build and maintain so you can shop with your own numbers instead of a sales page’s. No sign-up, no email address, and nothing you type ever leaves your browser.
The Tools
- Food & Water Planner — enter your household size and how many days you want to cover, and get the meals and gallons of water you actually need
- Power Station Size Calculator — tick the appliances you want to run in an outage and get the inverter watts and battery size to shop for
- Oxygen Absorber Calculator — pick your mylar bag size and food type, and get the absorber size and count for the whole batch
Why We Build These
Our reviews are scored on measured numbers — cost per serving, cost per gallon, usable capacity — because a preparedness purchase you cannot size is a purchase you cannot judge. The tools are the other half of that idea: they hand you the numbers for your household, and each one shows its method on the page, with typical published figures labelled as typical and the honest limits written out. It is the same research-desk standard behind How We Rate, applied to planning instead of products.
Run a tool first, then read the matching reviews with your numbers in hand — the starter kit reviews and the comparisons in each Preserve hub will mean a lot more.
Talk With Other Readers
Numbers only get you so far — the rest is other people’s hard-won experience. The Truly Preserved Community on Facebook is where readers compare notes on food storage, water, and backup power, show their setups, and ask the questions that decide what we research next. It’s free, it’s private, and new members are welcome.
More on the Way
One more is next in line: a long-term food storage calculator that breaks a 3-, 6-, or 12-month goal down into pounds of grains, beans, dairy, and staples. We’ll add it here when it’s ready.