Curing Salt (Nitrite) Calculator
Curing meat safely means delivering a precise, regulated amount of sodium nitrite, measured in parts per million of the meat weight. Curing salts are diluted blends (commonly 6.25 percent nitrite for cure No. 1) so they can be weighed accurately. This calculator converts a target nitrite ppm and your meat weight into the exact grams of curing salt to add, given the nitrite percentage on your product. The USDA FSIS sets legal ingoing nitrite limits by product type; always confirm the correct limit for what you are making. This tool does the arithmetic, not the food-safety decision.
Curing salt formula
nitrite needed (g) = meat (g) * ppm / 1,000,000
curing salt (g) = nitrite needed / (cure % / 100)
per kg = curing salt / meat (g) * 1000
cure as % of meat = curing salt / meat * 100
Parts per million means grams of nitrite per 1,000,000 g of meat. Dividing by the cure's nitrite fraction converts the pure nitrite target into the diluted product weight you actually weigh out.
Curing safety notes
- Cure No. 1 (Prague Powder No. 1) is 6.25 percent sodium nitrite by the federal product standard.
- 9 CFR 424.21 sets ingoing nitrite limits, commonly 156 ppm for comminuted products; other forms differ.
- Confirm the legal limit for your specific product before curing for sale.
- Sodium nitrite is toxic concentrated; weigh accurately on a precise scale.
- Cure No. 2 adds nitrate for long-cured products; enter its nitrite percentage.
Curing salt: frequently asked questions
What is curing salt No. 1?
Curing salt No. 1, often sold as Prague Powder No. 1 or pink curing salt, is a blend of sodium chloride with sodium nitrite. The federal regulation for the commercial product specifies 6.25 percent sodium nitrite by weight, the rest being salt plus a coloring agent. Enter the nitrite percentage printed on your product if it differs.
What ppm of nitrite is allowed?
Under USDA FSIS regulation (9 CFR 424.21), the ingoing limit for sodium nitrite in most comminuted cured meats is 156 parts per million; immersion-cured products and dry-cured products have their own limits, and bacon has specific rules. Parts per million here means grams of nitrite per million grams (per metric ton) of meat. Always follow the rule for your specific product.
How is the curing salt weight calculated?
Required nitrite mass = meat weight times target ppm divided by 1,000,000. The curing salt to add is that nitrite mass divided by the cure's nitrite fraction. For 1,000 g of meat at 156 ppm with a 6.25 percent cure: nitrite needed is 0.156 g, so curing salt is 0.156 / 0.0625 = 2.496 g.
Why is nitrite dangerous if overdosed?
Sodium nitrite is toxic in concentrated form, which is why it is sold heavily diluted in salt and dyed pink to prevent confusion with table salt. Exceeding the regulated ppm is both unsafe and unlawful for sold products. This tool helps you stay at or below your target ppm; verify against the FSIS rule for your exact product.
Does this cover curing salt No. 2?
The same arithmetic applies, but cure No. 2 also contains sodium nitrate for long dry-cured products. Enter the sodium nitrite percentage from your product label. The calculator sizes the cure to your target nitrite ppm regardless of which blend you use, as long as you enter the correct nitrite fraction.
Official sources
- eCFR: 9 CFR Part 424, Preparation and Processing Operations.
- USDA: Food Safety and Inspection Service.
Reviewed by the CalculatorHub team, edited by James Graham, 17 June 2026. See our methodology.