Cure #2 is process-specific
Cure #2 blends commonly contain sodium nitrite and sodium nitrate and are associated with long dry-cured products. That does not mean every product using Cure #2 should use one universal amount or timetable.
Quick answer
At the common 0.25% convention with a 6.25% nitrite + 4% nitrate label, 2.5 g of Cure #2 per kg of meat delivers 156 ppm ingoing nitrite and 100 ppm ingoing nitrate. Brands differ — some Cure #2 products carry only about 1% nitrate — so enter the percentages printed on your own package below.
Cure #2 Calculator
Calculates a Cure #2 amount from a cure-mix percentage of your meat weight, then reports the nitrite and nitrate it delivers. Enter both percentages from your own label.
Calculated result only: verify the exact product label, recipe/process and applicable requirements before use.
Assumptions, units and limits
- Brand formulations differ. Prague Powder #2 is commonly described as 6.25% sodium nitrite with up to 4% sodium nitrate; some products (for example certain Insta Cure #2 formulations) contain about 1% nitrate. Always enter the percentages printed on your package — the calculation is only as good as these two inputs.
- Nitrate is modeled as ingoing sodium nitrate. It is not converted to a nitrite-equivalent here: bacterial reduction during long cures depends on the process and cannot be predicted by this tool.
- 0.25% of meat weight with a 6.25% nitrite product delivers about 156 ppm ingoing nitrite. Long-cure recipes vary — your tested recipe is the controlling source.
- Not for bacon. U.S. regulations allow nitrite but not nitrate in bacon, and extension guidance warns against nitrate blends for home bacon. See the warning above.
- Formulation math only — it does not validate fermentation, drying or shelf stability.
For nitrite-only products, use the Cure #1 Calculator; for a full batch with salt and sugar, open the main calculator.
What is Cure #2?
Cure #2 is commonly formulated with both sodium nitrite and sodium nitrate. Oregon State University Extension describes Prague Powder #2 as a formulation offered with up to 4% sodium nitrate and 6.25% sodium nitrite, while also noting that proprietary products can differ. Verify the package you own before calculating.
Why nitrate changes the picture
Nitrate is not simply “extra nitrite.” In long curing processes it can participate in a slower conversion pathway, which is one reason Cure #2 appears in recipes for products such as certain dry-cured meats. The recipe/process still determines whether a nitrate-containing cure is appropriate.
Calculation model
Nitrate mass (mg) = Cure #2 mass (g) × nitrate fraction × 1,000
The calculator keeps those fractions explicit so the result can be checked rather than hidden inside a preset.
Cure #2 chart — grams by batch size at the 0.25% convention (156 ppm nitrite)
| Batch size | Cure #2 (grams) | ≈ Level tsp | Nitrite delivered | Nitrate delivered (4% label) |
|---|---|---|---|---|
| 1 lb (454 g) | 1.13 g | 0.20 tsp | 71 mg (156 ppm) | 45 mg (100 ppm) |
| 2 lb (907 g) | 2.27 g | 0.40 tsp | 142 mg (156 ppm) | 91 mg (100 ppm) |
| 5 lb (2.27 kg) | 5.66 g | 0.99 tsp | 354 mg (156 ppm) | 227 mg (100 ppm) |
| 10 lb (4.54 kg) | 11.33 g | 1.99 tsp | 708 mg (156 ppm) | 453 mg (100 ppm) |
| 25 lb (11.34 kg) | 28.32 g | 4.97 tsp | 1,770 mg (156 ppm) | 1,133 mg (100 ppm) |
| 1 kg | 2.50 g | 0.44 tsp | 156 mg (156 ppm) | 100 mg (100 ppm) |
| 2 kg | 4.99 g | 0.88 tsp | 312 mg (156 ppm) | 199 mg (100 ppm) |
| 5 kg | 12.48 g | 2.19 tsp | 780 mg (156 ppm) | 499 mg (100 ppm) |
With a 6.25% nitrite + 4% nitrate label, any dose that hits 156 ppm ingoing nitrite simultaneously delivers about 100 ppm ingoing nitrate — that ratio is fixed by the label fractions, not by the recipe. If your Cure #2 carries a different nitrate percentage (some products are closer to 1%), enter your own label values in the calculator above and the nitrate column changes accordingly.
Why you should not treat Cure #2 as an interchangeable Cure #1
- The ingredient composition can differ.
- The intended product/process can differ.
- Nitrate may be inappropriate for products that are later cooked under a specific regulatory or recipe framework.
- Commercial requirements are product- and process-specific.
Bacon warning
USDA FSIS states that bacon may use nitrite but not nitrate, and describes different ingoing nitrite limits for dry-cured versus pumped or immersion-cured bacon. Do not use a generic Cure #2 assumption for bacon; follow a tested, product-specific formulation.
Common mistakes
- Assuming 4% nitrate is present in every Cure #2 product.
- Using a Cure #2 formula for a recipe that calls for Cure #1.
- Looking at total cure-mix weight without checking the nitrite/nitrate fractions.
- Assuming a PPM calculation validates fermentation, drying or shelf stability.
Worked example: 1 kg at 0.25% mix
Cure #2 (g) = 1,000 g × 0.25% = 2.50 g. Nitrite (mg) = 2.50 × 0.0625 × 1,000 = 156.3 mg → 156.3 ppm ingoing nitrite on a 1 kg basis. Nitrate (mg) = 2.50 × 0.04 × 1,000 = 100.0 mg → 100 ppm ingoing nitrate with a 4% product. The same 2.5 g with a 1% nitrate brand would deliver only 25 ppm nitrate — the calculator reports both numbers so the difference is visible before you mix.
Frequently asked questions
How much Cure #2 per kg of meat?
Many long-cure recipes use about 0.25% of meat weight — 2.5 g per kg — delivering roughly 156 ppm ingoing nitrite with a 6.25% product. That is a common convention, not a rule: long-cure formulations vary a lot, so the tested recipe you follow is the controlling source, and the label percentages of your actual product are the required inputs.
Is Cure #2 always 4% nitrate?
No. Prague Powder #2 is commonly described as 6.25% sodium nitrite with up to 4% sodium nitrate, but other products differ — for example, some Insta Cure #2 formulations contain about 1% nitrate. This is exactly why the calculator asks for both percentages from your label instead of assuming a standard blend.
Can I use Cure #2 for bacon?
Not for U.S.-style bacon. Federal regulations allow nitrite but not nitrate in bacon, with method-specific ingoing nitrite limits, and Oregon State University Extension likewise advises against nitrate-containing blends for home bacon. Use Cure #1 and the method-appropriate target instead — see the Bacon Curing Salt Calculator.
Why does Cure #2 contain nitrate at all?
Nitrate is a slow-release reserve. Over weeks to months in long dry-cured products, bacteria convert some nitrate into nitrite, replenishing nitrite that has been depleted. That slower pathway is why nitrate-containing blends appear in recipes for products aged a long time — and why they are not interchangeable with nitrite-only Cure #1.
Does the nitrate ppm number tell me the converted nitrite?
No. The calculator reports ingoing sodium nitrate on the entered basis. How much of it converts to nitrite depends on microbial activity, time, temperature, salt level and pH in your actual process — it cannot be predicted from the formulation alone.
Using Morton®-style Tender Quick instead?
Tender Quick carries roughly 0.5% nitrite plus 0.5% nitrate — far weaker than Cure #2 — and its printed spoon directions reflect that. Use the Morton Tender Quick calculator or read the full Tender Quick vs Cure #1 comparison before swapping products.
Sources
Oregon State University Extension
Their home-bacon publication explains common Cure #2 composition and cautions around product-specific proprietary blends.
USDA FSIS
Official bacon-specific reference for nitrite use and method-specific limits.
Need the math?
Use the main tool with the exact nitrite/nitrate percentages printed on your Cure #2 package.