Jam & Jelly Calculator

Calculate sugar and approximate yield for jam from your fruit weight.

Usage Tip

Sugar acts as a preservative, so lower-sugar jams keep for less time once opened.

Sugar Needed
— g sugar
For the batch
THE MATH
sugar = fruit × ratio; yield ≈ (fruit + sugar) × 0.7
Standard jam uses equal weights of fruit and sugar; less sugar needs added pectin.
Yield is approximate; water boils off during cooking to reach setting point.
Scroll to Top

The calculators and tools on Formula Factory are provided for general guidance and informational purposes only. Results are estimates based on standard formulas and the values you enter — they do not constitute professional engineering, electrical, or architectural advice. Always verify calculations with a qualified professional before making decisions for any safety-critical, code-compliance, or commercial application. Formula Factory makes no representations or warranties as to the accuracy or completeness of any result, and accepts no liability for errors, omissions, or any outcomes arising from reliance on this information.