Canning Yield Calculator
Quart and pint jars from produce pounds, NCHFP rates.
What it does
Canning starts with arithmetic at the bushel. Twenty-one pounds of tomatoes fill seven quarts at 3 lb per quart, nine pounds of beans fill four and a half quarts at 2, and peaches split the difference at 2.5. Yields set jar counts before jars touch heat.
The tool above runs NCHFP yield math for three staples. Enter produce pounds and it prints quarts, pints, and the safe method line: water-bath for acidified tomatoes and peaches, pressure only for beans. Defaults show the tomato case at 7 quarts and 14 pints.
Federal guides supply the rates. NCHFP pack tables give 21 lb per 7 quarts of tomatoes, 14 per 7 of beans, and 17.5 per 7 of peaches, with bushel yields behind each. Clemson matches tomatoes with acid rules: 2 Tbsp lemon juice per quart, 1 per pint.
Method lines are safety lines, not suggestions. Low-acid beans in a water bath risk botulism at any time or temperature, while tomatoes need their acid dose to qualify for the bath. Process jars at tested times and pressures only.
How to use
- Pick tomatoes, beans, or peaches.
- Weigh the produce in pounds.
- Read quarts first, then pints.
- Read the canning method line.
- Acidify tomatoes per jar size.
- Follow tested NCHFP times.
Formula
- lb
- Produce weight in pounds.
- rate
- Pounds per quart jar by food.
Rates divide NCHFP pack figures (21/7 tomatoes, 14/7 beans, 17.5/7 peaches) with Clemson matching tomatoes.
Worked example
Example: 21 lb tomatoes
Defaults: 21 lb tomatoes.
- Inputs: 21 lb tomatoes.
- Rate: 3.0 lb per quart (NCHFP 21/7).
- Quarts: 21 / 3.0 = 7.
- Pints: 7 x 2 = 14.
- Method: water-bath OK if acidified. Tool shows 7 quarts, 14 pints.
Reference table
| Food | lb/quart | Method |
|---|---|---|
| Tomatoes | 3.0 | Water-bath if acidified |
| Green beans | 2.0 | Pressure only |
| Peaches | 2.5 | Water-bath |
Limits
- Yield math only. Processing times need NCHFP tables.
- Three foods only; others have own rates.
- Assumes sound ripe produce at stated pack.
- Altitude adjusts pressures and times.
Common mistakes
- Water-bathing green beans.
- Skipping tomato acidification.
- Guessing yields instead of weighing.
- Reusing lids across seasons.
- Inventing processing times.
Try it yourself
Quick checks. Answers sit tucked under each question.
9 lb green beans?
9 / 2.0 = 4.5 quarts. Pints 4.5 x 2 = 9. Method pressure canner only.
12.5 lb peaches?
12.5 / 2.5 = 5 quarts. Pints 5 x 2 = 10. Method water-bath OK.
Questions
How are jars figured?
Pounds over the per-quart rate: tomatoes 3.0, beans 2.0, peaches 2.5. Here 21/3 = 7 quarts.
Water bath or pressure?
Fruit and acidified tomatoes take boiling-water baths; low-acid vegetables like beans need pressure canners only.
How do I acidify tomatoes?
2 Tbsp bottled lemon juice per quart (1 per pint), or half tsp citric acid per quart.
Quarts to pints?
Double the quarts: 7 quarts fill 14 pints. Pints process faster but need tested times.
What does a bushel fill?
Yes. A bushel of tomatoes (53 lb) yields 15-21 quarts; beans (30 lb) yield 12-20.
Can I invent processing times?
No. Only tested NCHFP times and pressures; improvising invites botulism.
Sources
- NCHFP: Tomatoes (21 lb / 7 qt, acid rule)
- NCHFP: Snap Beans (14 lb / 7 qt, pressure only)
- NCHFP: Peaches (17.5 lb / 7 qt)