Pressure Canning at High Altitude: What Changes by Machine

If you live up in the mountains, canning takes one extra step of care. You need to know which rule belongs to your machine. Much of the confusion online comes from using one machine's rule on another.

Why does altitude matter?

The USDA says it in one line: temperatures inside a canner are lower at higher altitudes. Water boils at a lower temperature as you climb. The National Center for Home Food Preservation (the US canning experts at the University of Georgia, "the National Center" from here on) says lower boiling temperatures are less effective at killing germs. High heat held long enough does the work. Pressure doesn't kill germs directly. It's just how a canner reaches that heat.

So the two methods fix this differently. In a pressure canner, you raise the pressure. In a boiling water canner, you add time. The National Center says sea-level times may not be enough from about 1,000 feet up. It says the wrong pressure or time for your altitude can lead to spoilage.

Who adjusts how?

These are what each maker and expert says. The rule for one type does not carry over to another.

• Stovetop canner with a dial gauge (a clock-face pressure dial): You raise the pressure using the USDA table. It has four altitude bands.
• Stovetop canner with a weighted gauge (a small weight that rocks or jiggles): You raise the pressure using the USDA table. It has two bands: at or below 1,000 feet, and above.
• Presto Precise, pressure canning: Presto says no change is needed, because the sensor holds the temperature. Nobody outside the company has confirmed that.
• Presto Precise, water bath: The time changes with altitude, says Presto.
• NESCO NPC-9 cooker-canner: Black regulator at or below 1,000 feet, green above. NESCO does not recommend use over 7,500 feet.
• Ball EasyCanner, electric water bath: Water bath always needs a change for altitude. Follow your tested recipe.
• Electric multi-cooker (Instant Pot): Not for pressure canning. The National Center says you can't use the same pressure and time at every altitude.

Where are the official tables?

We print no pressure table on this site, on purpose. A wrong number copied from a website can lead to under-heated food. These numbers already have an owner.

• The USDA tables: each food in the USDA Complete Guide has its own table by canner type and altitude. Guide 1 explains the basics.
• How to read them: the National Center's page on choosing the right processing time explains the bands.
• Your altitude: ask your local county extension agent (free local food-safety advice) if you don't know it.

Dial or weighted gauge at altitude?

Penn State says both types preserve food safely when used correctly. The difference shows up in the mountains. The National Center says weighted gauges can't adjust precisely for altitude. They step up in one jump above 1,000 feet. Penn State says dial gauges allow finer changes at high altitude. Presto's guide says the same of its dial-gauge canners above 2,000 feet. The trade-off is upkeep. The National Center says to check a dial gauge for accuracy before use each year, and many county extension offices can help.

Our pick for stovetopAd

Presto

Presto 23-Quart Stovetop (01781)

A pot for your stove, the kind the USDA's canning steps were written for.

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Type

Stovetop pressure canner with dial gauge

Pressure canning

Yes

Water bath

Yes, quarts and smaller, per Presto

Liquid capacity

23 quarts

Jars per load

7 quarts, or 20 regular-mouth pints stacked

Altitude

You raise the pressure by altitude from the USDA tables. Water bath times also change with altitude.

Price class

Mid-range

Stated in: Presto Canner Comparison Guide (2025), read 2 November 2026

Why here: A stovetop canner with a dial gauge, the kind that follows the USDA tables by altitude band. It is our main pick for most readers.

Best for: You want to pressure can low-acid foods (vegetables, meat, chicken, fish) and can stay near the stove.

• The National Center's advice was written for stovetop canners
• Seven quart jars, or up to 20 regular-mouth pints stacked, says Presto
• Also works as a water bath canner for quarts and smaller, says Presto
• Works on gas and on electric coil and smooth-top ranges, says Presto

• You watch the gauge and adjust the heat yourself
• The dial gauge needs an accuracy test every year, says Presto
• Presto does not list induction for this pot. The 01784 is its induction version

View on Amazon*(paid link to Amazon, opens in a new tab)Ad · paid link · check price & delivery on AmazonLearn more

For more choices, see our stovetop canner page. The gauge comparison goes through the two types.

Can you trust the sensor claim?

Presto's explanation is simple: its canner holds 240°F whether you live at 1,000 or 10,000 feet, so altitude doesn't affect the pressure method. North Dakota State describes the machine the same way, and Penn State says it adjusts for altitude. The USDA does say high heat is what kills germs. That doesn't by itself show what a machine reaches inside your jars.

What's missing is the data. Nobody outside the company has published test results for Presto Precise canners. A sensor in the canner doesn't measure inside your jars. Presto's claim also covers pressure canning only. Its own FAQ says water bath needs the altitude change in the USDA guide. More on our Presto Precise page.

What did the multi-cooker research find?

Utah State's extension service ran three electric pressure cookers it did not name, at about 2,900, 4,500 and 7,100 feet. It put temperature loggers in the jars. Many batches were under-heated, more of them at higher altitude. Results varied even for the same food, cooker and altitude. It says not to can low-acid food in such cookers.

This study covers cookers, and their models are not named. It says nothing about any canner we can name. That's why Instant Pot canning has its own page.

What should you do above 1,000 feet?

• Find your altitude before you shop, and check it against the manual of any machine you're considering.
• Read the altitude part of your manual. On a NESCO, that includes which regulator is fitted. See the NESCO page. Read are electric pressure canners safe too.
• Use the tested recipe's own altitude line. Water bath recipes have one too.
• Compare your options. Our electric vs. stovetop comparison treats altitude as one deciding point.