Freeze Dry Math

The home freeze-drying guide

Preserve the season, beautifully.

How much fits on a tray, how long it will run, what it costs in power and bags, which oxygen absorber to use, and how much water to add back. Plus prep notes for 72 foods, each written for that food.

Open the calculatorsFreeze drying times chart
A wooden harvest basket filled with assorted tomatoes, okra, shallots, and fresh herbs
A bushel of peaches (48 lb)≈ 5 batcheson a Medium
Photo: Zoe Richardson on Unsplash
91%of a strawberry is water. 1 lb dries to about 1½ oz.
13–35 his a typical batch, says Harvest Right. Pineapple can take 50.
500 ccoxygen absorber for a gallon bag of loose freeze-dried food.
0 °Fand below before drying starts. Bacteria survive it: cook meat and eggs.

Calculators

All calculators →
01Tray Capacity and Harvest PlannerHow much of a food fits per tray and per batch on your model, and how many batches a harvest takes.02Batch Time EstimatorA realistic hour range for a food, adjusted for thickness, load and room temperature.03Freeze-Dried Yield and Bag PlannerWhat fresh food weighs after drying, and how many bags it will fill.04Is It Dry? Weight CheckTwo weighings tell you whether a batch is really done, and how close it is to its expected dry weight.05Rehydration Water CalculatorHow much water to add back to any freeze-dried food, by weight or by water content.06Oxygen Absorber CalculatorWhich absorber size, or combination, each mylar bag or jar needs.07Freeze Dryer Cost per BatchElectricity, bags, absorbers and oil per batch, per pound fresh and per ounce dried.08Freeze Dryer Payback CalculatorHow many batches until the machine pays for itself versus buying freeze-dried food.09Freeze-Dried Candy Pricing CalculatorCost per bag, fees and profit per batch for people who sell freeze-dried candy.

Most-asked foods

All 72 foods →
Sliced strawberries
Strawberries22–30 h Excellent
A grid of brown chicken eggs in a molded cardboard carton
Eggs22–32 h Good
Half peeled banana fruit
Bananas20–30 h Excellent
Three ears of fresh corn on a wooden surface
Sweet corn18–26 h Excellent
Roasted chicken on white ceramic plate
Chicken20–30 h Excellent
Skittles in a row
Skittles2–6 h Good
Person pours milk into glass
Milk30–40 h Good
Two whole peaches and one halved peach with a pit on a white surface
Peaches24–34 h Good
A bowl of chili next to other bowls of food
Chili24–34 h Excellent
A bowl of yogurt with a spoon in it
Yogurt20–30 h Excellent
A pile of sliced apples sitting on top of a table
Apples18–26 h Excellent
Pineapple fruit on white table
Pineapple36–52 h Tricky

Guides

All guides →
Person holding a pot on a single camp burner
Making Your Own Freeze-Dried Backpacking MealsWhich home meals freeze-dry and rehydrate well on the trail, how to portion and pack them, how much water each needs, and the fat and safety limits to respect.
Assortment of dried fruits in market stalls
Freeze Dryer vs Dehydrator: Which One Makes Sense for YouCost, texture, shelf life, nutrition, speed and which foods each handles best, with the break-even math on whether a $2,000+ freeze dryer is worth it over a $100 dehydrator.
Two jars of freeze-dried yogurt snacks
How a Home Freeze Dryer Works, Step by StepWhat happens inside the chamber during freezing, primary drying and final dry, why batches take 20 to 40 hours, and how to run a sensible first batch.

What this site is

Freeze Dry Math is a set of calculators and food notes for people who own, or are thinking about buying, a home freeze dryer. Machine figures come from the makers’ published specs. Water content comes from USDA FoodData Central. Food safety advice follows university extension services, which in 2026 published the most careful guidance yet on what home freeze-drying can and can’t do.

We are not affiliated with Harvest Right or any manufacturer, and we say plainly when a number is a rule of thumb rather than a measurement. More about us.