A canning recipe scaler lets you adjust preserving recipes by jar count while keeping safety-critical ratios intact. Whether you are doubling a batch of strawberry jam or halving a salsa recipe, this tool scales every ingredient proportionally and warns you about acid, salt, and processing-time rules that keep home-canned food safe from botulism and spoilage.
Canning Safety Reminders
- Do NOT alter vinegar or lemon juice ratios — acidity is critical for safety.
- Do NOT reduce salt in fermented or brined recipes.
- Processing time does NOT change with batch size — only adjust for jar size and altitude.
Batch Settings
Ingredients
Scaled Recipe
Processing Time Reference
Typical times at 0–1,000 ft elevation. Always follow your tested recipe.
| Product | Half-Pint | Pint | Quart | Method |
|---|
Altitude Adjustment (Water Bath)
Pectin Calculator
High-pectin fruits (apples, citrus, cranberries) may need less. Low-pectin fruits (strawberries, peaches, cherries) may need more.
How to Use the Canning Recipe Scaler
Home canning lets you preserve the harvest and enjoy seasonal flavors year-round, but scaling recipes up or down requires more care than regular cooking. Changing batch size is straightforward for most ingredients, yet safety-critical components like vinegar, lemon juice, and salt must maintain their tested ratios to prevent botulism and spoilage. Our free canning recipe scaler handles the maths while keeping you safe.
Step 1: Set Your Jar Yield
Enter the number of jars the original recipe makes in the Original yield field and the number you want to produce in Target yield. Select the jar size — half-pint, pint, or quart — to match your recipe. The scaler calculates the multiplier from these two numbers. If you are new to a recipe, try one of the five built-in presets (strawberry jam, dill pickles, salsa, apple butter, or tomato sauce) to see a complete ingredient list with typical yields.
Step 2: Enter or Edit Ingredients
Each ingredient row has three fields: amount, unit, and name. The amount field accepts whole numbers, decimals, and fractions like 1/2 or 1 1/2. Choose from common canning units including cups, pounds, ounces, tablespoons, and teaspoons. Click Add ingredient to insert more rows as needed, or use the × button to remove a row.
Step 3: Scale and Review Safety Warnings
Click Scale Recipe to apply the multiplier. The results section shows each ingredient with its new amount. If the recipe contains vinegar, lemon juice, citric acid, or salt, a safety warning appears reminding you that these ingredients must not be reduced below tested levels. Processing time does not change with batch size — it depends only on jar size and altitude.
Step 4: Check Processing Times and Altitude
The processing time reference table lists typical water bath and pressure canning times for common products at each jar size. If you live above 1,000 feet, use the altitude adjustment guide: add 5 minutes for 1,001–3,000 feet, or 10 minutes above 3,000 feet for water bath canning. Always follow a tested recipe from a trusted source such as the USDA Complete Guide to Home Canning or your local cooperative extension.
Step 5: Pectin, Print, and Preserve
For jam and jelly recipes, use the built-in pectin calculator to estimate how much powdered or liquid pectin you need based on cups of fruit. Once you are satisfied with the scaled recipe, click Copy to copy the ingredient list to your clipboard or Print to produce a clean printout for the kitchen. All calculations happen in your browser — nothing is stored or sent anywhere.
FAQ
Is this canning recipe scaler really free?
Yes, the canning recipe scaler is completely free with no account, no ads-walls, and no limits. Everything runs locally in your browser so you can use it even while working in your kitchen offline.
Is my recipe data safe and private?
Absolutely. All calculations happen entirely in your browser. Your recipes and ingredient lists are never sent to any server, stored, or shared with anyone.
Can I change the vinegar or lemon juice amount when scaling?
No. Acidity is critical for safe canning. The scaler flags vinegar, lemon juice, and citric acid as safety-critical ingredients. You should never reduce acid levels below the tested recipe ratio, as this can create unsafe conditions for botulism.
Does processing time change when I double a canning recipe?
No. Processing time depends on jar size and altitude, not batch size. Doubling a recipe means you fill more jars, but each jar is processed for the same amount of time. Use our altitude adjustment reference to add time if you are above 1,000 feet.
What jar sizes does the scaler support?
The scaler supports the three standard canning jar sizes: half-pint (8 oz), pint (16 oz), and quart (32 oz). Select the jar size that matches your recipe and target yield for accurate scaling.
How does altitude affect canning processing times?
For water bath canning, add 5 minutes of processing time if you are between 1,001 and 3,000 feet elevation, and add 10 minutes above 3,000 feet. Pressure canning adjustments vary by dial or weighted gauge type. Always verify with your local extension office.
How much pectin do I need for my jam recipe?
The built-in pectin calculator estimates the amount of powdered or liquid pectin you need based on cups of fruit. Generally, 4 cups of fruit use about 1 packet (1.75 oz) of powdered pectin or 3 oz of liquid pectin. High-pectin fruits like apples need less.
Can I use this for pressure canning recipes too?
Yes. The scaler works for any canning recipe regardless of processing method. The processing time reference table includes both water bath and pressure canning times by jar size. Always follow a tested recipe from a trusted source like the USDA or your local cooperative extension.