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Preserve it! Series: How to Test a Pressure Canner Dial Gauge at Home

  • May 6, 2026

Canning Basics: Use a weighted gauge to test a dial gauge's accuracy. 

Pressure canner dial gauges* should be tested annually for accuracy to ensure that food is not under-processed (and thus potentially unsafe) or over-processed (resulting in lower quality food). Many Cooperative Extension services will test pressure canner gauges at no or minimal cost, or provide advice on where to send your dial gauge for testing. If your pressure canner has a both a dial gauge and a weight, it can be tested at home. 

How to test the accuracy of the dial gauge

  1. Fill your canner with water according to the manufacturer’s instructions. Add a minimum load of 4 pint jars or 2 quart jars filled with water (no lids are necessary). Heat and vent the pressure canner normally.
  2. Place the 5-lb weight on the vent pipe and bring to pressure (as determined by the appropriate rocking rate of the weight). Set timer for 10 minutes. Read the dial gauge, and write down the pressure reading.
  3. Add the 10-lb weight and bring to pressure. Set timer for 10 minutes. Read the dial gauge, and write down the pressure reading.
  4. Add the 15-lb weight and bring to pressure. Set timer for 10 minutes. Read the dial gauge, and write down the pressure reading.

If the gauge reading is off by 2 pounds or more in either direction, it needs to be replaced. 

*Many pressure canners are actually weighted-gauge canners and have dial gauges for use only as a reference tool. For example, All American pressure canners are weighted-gauge canners; pressure is determined by the rocking of the weight and the dial is only to use as a reference. Presto canner models equiped with a dial are dial-gauge pressure canners (which can be converted to a weighted-gauge canner by using their 3-piece weighted gauge purchased separately; check to be sure it fits your canner model).

For further information on pressure canning, visit the National Center for Home Food Preservation (NCHFP) or contact your local Cooperative Extension office. 

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Updated July 2025