Free tool for jar meals and batch cooking
Jar meal batch scaler and cost per serving
Divide the jars you want by the jars the recipe makes, then multiply every ingredient by that factor. A recipe for 4 jars scaled to 10 jars uses a factor of 2.5: 1 cup becomes 2.5 cups. If the 4-jar batch costs $9.20, 10 jars cost $23.00, which is $2.30 per jar or $1.15 per serving at 2 servings per jar.
Last updated 2026-10-30.
- Scale factor
- ×
- Batch cost
- Per jar
- Per serving
Enter positive numbers for jars and servings.
Example scenarios
Three sets of example inputs worked through the same formulas as the calculator above. They are illustrations, not averages or statistics.
| Scenario | Inputs (recipe makes 4 jars, $9.20, 2 servings per jar) | Factor | Total cost | Per jar | Per serving |
|---|---|---|---|---|---|
| Low | 2 jars wanted | 0.5 | $4.60 | $2.30 | $1.15 |
| Typical | 10 jars wanted | 2.5 | $23.00 | $2.30 | $1.15 |
| High | 24 jars wanted | 6 | $55.20 | $2.30 | $1.15 |
Method: Factor = jars wanted ÷ jars the recipe makes; every amount and cost is multiplied by the factor; cost per jar = total cost ÷ jars wanted; per serving = cost per jar ÷ servings per jar. Figures checked against the same formulas on 2026-10-30.
How the scaler works
Enter how many jars your recipe makes and how many jars you want to fill. The scale factor is the second number divided by the first. Every ingredient amount is multiplied by that factor, in whatever unit you typed it: cups stay cups, grams stay grams. The tool never converts between volume and weight, because that depends on the ingredient.
If you also enter what each ingredient cost you for the amount in the original recipe, the tool adds those costs, scales them the same way and divides by jars and by servings per jar.
Worked example
A recipe makes 4 jars and you want 10. The factor is 10 ÷ 4 = 2.5. An ingredient listed as 1 cup becomes 2.5 cups; 120 g becomes 300 g. If the ingredients for the 4-jar recipe cost $9.20 in total, 10 jars cost 9.20 × 2.5 = $23.00. That is $2.30 per jar, and at 2 servings per jar, $1.15 per serving.
Getting the cost per serving right
Use the price of the amount you actually use, not the price of the whole bag. If a 5 lb bag of rice cost $6 and the recipe uses about a tenth of it, enter $0.60 for that line. Spices and small items add up across a big batch, so it is worth entering them too. The total updates as you type, so you can compare a cheaper ingredient swap straight away.
Rounding for real measuring spoons
Scaled amounts are shown with up to two decimals. In the kitchen, round to the nearest measure you own. For small amounts such as salt or spices, rounding changes the taste more than for rice or beans, so taste a test jar before making a large batch.
What this tool does not do
It only does arithmetic. It says nothing about food safety, storage or shelf life, and it does not check whether a recipe is safe to store in jars. Use a tested, sourced recipe for that.
Questions
Can I scale down as well as up?
Yes. If the recipe makes 12 jars and you want 3, the factor is 0.25.
Does it convert cups to grams?
No. Converting volume to weight depends on the ingredient, so the tool keeps your units.
Does this page store my recipe?
No. The math runs in your browser; nothing is sent or saved.
We are also planning a paid product: Jarshelf, Shelf-stable jar meals with tested ratios. It is not available yet; its page shows the planned price, and reserving charges nothing. See the planned product