CanningDates › Jar yield calculator
Weigh the harvest, count the jars
How many jars will my harvest fill?
Pick the produce, type the pounds, and see the quarts and pints before you're standing in the jar aisle. Every figure is USDA's published quantity line — about 21 lb of tomatoes to a 7-quart canner load — divided for your harvest, with one spare jar always on the list.
No produce scale? Step on the bathroom scale holding the basket, then without it — the difference is your harvest.
Water bath
Tomatoes, whole or halved
- HARVEST
- 21 LB
- QUART JARS
- ≈7
- PINT JARS
- ≈14.5
- BUY
- 8 QT · 16 PT
USDA figures about 21 lb per 7-quart canner load and 13 lb per 9-pint load for tomatoes, whole or halved — about 3 lb to the quart.
canningdates.com
canningdates.com — jar counts divided from USDA's published canner-load quantity lines. Low-acid foods must be pressure canned.
About 3 lb per quart. Needs added lemon juice or citric acid in every jar; pressure options are also published — follow the tested recipe.
Shopping count: 8 quart jars or 16 pint jars, a new flat lid for every jar, and rings to match (sound jars and rings reuse for years; flat lids don't). That's the fill rounded up plus one spare, because a chipped rim or a lid that won't seal shouldn't end the canning day.
Real kitchens vary: pack style and produce size swing the jar count — a hot pack fits more food per jar than a raw pack, small fruit trims leaner than large — so buy a little extra and let the last jar surprise you.
Working backward: to fill a 7-jar canner load of quarts you'd want about 21 lb of tomatoes, whole or halved; a 9-jar load of pints, about 13 lb.
Where the numbers come from — the whole table
Every NCHFP "how do I can" page opens with a quantity line: how many pounds fill a canner load of 7 quarts, and of 9 pints. The picker above divides your harvest by those lines and does nothing else. Here is the entire set, no JavaScript required — divide, round up, add a spare jar, and you've matched the calculator by hand.
| Produce | Canner | Lb per 7 quarts | Lb per 9 pints | ≈ lb per quart |
|---|---|---|---|---|
| Fruit | ||||
| Apples, sliced | Water bath | 19 | 12¼ | ≈2.7 |
| Applesauce | Water bath | 21 | 13½ | ≈3 |
| Berries | Water bath | 12 | 8 | ≈1.7 |
| Cherries, unpitted | Water bath | 17½ | 11 | ≈2.5 |
| Peaches | Water bath | 17½ | 11 | ≈2.5 |
| Pears | Water bath | 17½ | 11 | ≈2.5 |
| Plums | Water bath | 14 | 9 | ≈2 |
| Vegetables | ||||
| Beans, snap or green Low-acid — pressure canner required. | Pressure only | 14 | 9 | ≈2 |
| Beets, without tops Low-acid — pressure canner required (pickled beets are a separate tested recipe). | Pressure only | 21 | 13½ | ≈3 |
| Carrots, without tops Low-acid — pressure canner required. | Pressure only | 17½ | 11 | ≈2.5 |
| Corn, whole kernel (in husks) Weight is corn still in the husk. Low-acid — pressure canner required. | Pressure only | 31½ | 20 | ≈4.5 |
| Cucumbers, pickling (whole dills) Water bath as tested PICKLES only — plain cucumbers have no tested plain-pack process. | Water bath | 14 | 9 | ≈2 |
| Peas, green (in pods) Weight is peas still in the pod. Low-acid — pressure canner required. | Pressure only | 31½ | 20 | ≈4.5 |
| Potatoes, white Low-acid — pressure canner required. | Pressure only | 20 | 13 | ≈2.9 |
| Spinach and other greens Low-acid — pressure canner required. | Pressure only | 28 | 18 | ≈4 |
| Pumpkin and winter squash, cubed Cubes only — NEVER can puree or mashed pumpkin; no tested process exists. | Pressure only | 16 | 10 | ≈2.3 |
| Sweet potatoes Low-acid — pressure canner required. | Pressure only | 17½ | 11 | ≈2.5 |
| Tomatoes | ||||
| Tomatoes, whole or halved About 3 lb per quart. Needs added lemon juice or citric acid in every jar; pressure options are also published — follow the tested recipe. | Water bath | 21 | 13 | ≈3 |
| Tomato juice Needs added lemon juice or citric acid in every jar. | Water bath | 23 | 14 | ≈3.3 |
Frequently asked questions
Why did I get fewer jars than the chart said?
The published lines are averages — the tomato page reads "an average of 21 pounds is needed per canner load of 7 quarts." Hot-packed food shrinks before it goes in, so more fits per jar and fewer jars come out; raw pack runs the other way. Small or bruised produce trims away more, too. Fewer jars than the table doesn't mean anything went wrong — it means your kitchen isn't an average.
What exactly is a canner load?
It's the unit USDA states its quantities in: the jars one canner processes at a time, written as 7 quarts or 9 pints. Every produce page carries a quantity line — snap beans, for instance, average 14 lb per 7-quart load and 9 lb per 9-pint load — and this page divides your harvest weight by those same lines. That's the whole trick.
Should dense foods go in quarts or pints?
Use the jar sizes the tested recipe lists, at the process time listed for that size. Where a recipe's table has no quart column, no tested quart process exists — dense, slow-heating packs are exactly where the testing matters — and there is no safe way to invent one. The pint figures above still cover the planning.
Why do corn and green peas take so many pounds?
Because the published weights are for corn still in the husk (31½ lb per 7-quart load) and peas still in the pod (31½ lb). Husks, cobs, and pods weigh plenty, and none of it lands in the jar. Weigh before shucking or shelling and the figures line up.
Do I need new jars, lids, and rings every season?
Jars and screw rings serve for years so long as rims are chip-free and rings aren't rusted. Flat lids are the exception: the sealing compound is a one-use part, so buy new flats every time. That's also part of why the shopping count adds a spare jar — a lid that won't seal on canning day shouldn't stop the batch.
Why do some rows say "pressure only"?
Those are low-acid foods. They aren't acidic enough to stop botulinum spores, and boiling-water temperature doesn't destroy the spores — only the hotter steam inside a pressure canner does, which is why no length of water-bath time makes those jars safe. The food-by-food ruling lives at water bath or pressure.