Wash, peel, rewash, and slice or dice carrots.
Hot pack: cover with boiling water, bring to a boil, and simmer 5 minutes. Raw pack: fill jars tightly with raw carrots.
Add salt if desired and hot cooking liquid or fresh boiling water, leaving 1-inch headspace. Adjust lids.
Pressure process pints 25 minutes or quarts 30 minutes.
Dial gauge: 11/12/13/14 psi at 0–2,000/2,001–4,000/4,001–6,000/6,001–8,000 ft. Weighted gauge: 10 psi through 1,000 ft; 15 psi above.