Tools & Calculators

Practical, free calculators to help you plan and measure what your family actually needs. No guessing. No fluff.

Long-Term Food Storage Calculator

Free

Figure out exactly how much wheat, legumes, baking essentials, vitamins, and freeze-dried meals your family needs for up to a year. Adjust household size and duration, and the sheet calculates quantities and estimated cost.

  • Covers staple foods + freeze-dried meals
  • Scales by number of adults and children
  • Breaks down cost by category
Open Calculator

Backup Power Needs Calculator

Free

Input every electrical device in your home and this calculator tells you what generator size to buy, how much battery capacity you need, the right solar panel array, and how much fuel to store. Includes priority tiers so you know what to cut first when fuel runs low.

  • Generator, battery & solar sizing
  • Fuel consumption estimates
  • Medical device priority flagging
Open Calculator

Make It Yours

These sheets open in view-only mode. To enter your own numbers:

  1. Open the calculator and sign in to your Google account.
  2. Click File → Make a copy.
  3. Your personal copy saves to your Google Drive — edit freely.

Want something way more powerful?

The Primal Defender app has these tools built in — plus Atlas, your personal AI coach.

Spreadsheets get the job done, but Atlas can have a conversation about your specific situation, make exact product recommendations from our trusted partners, and track your progress across all 11 domains.

“Atlas, what generator do I need for a family of 5 with a CPAP machine?”