Pressure Canning Calculator

Weighted-gauge and dial-gauge pressure canners are read completely differently. A weighted-gauge canner only has a small set of fixed weights, so NCHFP guidance has it step directly from 10 PSI (at or below 1,000 ft) to 15 PSI (above 1,000 ft) with nothing in between. A dial-gauge canner has a continuous needle reading, so its guidance starts at 11 PSI for 0-2,000 ft and rises by 1 PSI for every additional 2,000 ft of elevation. Using the wrong gauge type's PSI on your actual canner risks under-processing.

No. NCHFP's "Selecting the Correct Processing Time" states that process times for half-pint and pint jars are the same, as are times for 1-1/2-pint and quart jars, so this calculator returns the pint time for both Half-Pint and Pint. The rule only runs one way: you may put food in a smaller jar and process it for the larger jar's time, but you may never shorten a published time because the jar is smaller. Heat penetration to the cold spot at the jar's center is not proportional to jar volume, so a shorter time on a half-pint is not a safe substitution.

Each entry in the Food list carries the pint and quart times published on that food's own page at the National Center for Home Food Preservation. They are not category averages -- published vegetable times alone run from 20 minutes for snap beans to 70 minutes for spinach and other greens, which is why a single "vegetables" figure cannot be safe. If the food you are canning is not in the list, do not substitute the nearest entry: look up its own tested NCHFP, USDA, or Cooperative Extension recipe, since pack style, piece size, and whether the meat is bone-in all change the correct time.

This calculator intentionally stops at 10,000 ft because that is the top of NCHFP's published altitude-adjustment tables for standard pressure canners -- there is no reliable published PSI figure to extrapolate beyond it. If you can at a higher elevation, contact your local Cooperative Extension office for guidance specific to your equipment and altitude rather than assuming the trend shown here continues linearly upward.