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Jam Cooking Calculator Support

Have you already discovered the Jam Cooking Calculator, your ultimate jam-making helper?

If you've landed here, you're a fan of delicious jam and already know the advantages of the Jam Cooking Calculator.


Then you also know that we do not collect user data, there are no links to third parties or advertising, and that there are no costs for you—you know that you can simply make delicious jam!

However, you have arrived at this page because you have questions or suggestions? Please feel free to browse or contact us so that we can assist you further.

Enjoy the rest of your journey through the delicious world of jam.


How can I influence the sweetness of my jam?

Option 1:
Play around with the ratio of fruit to jam sugar or Gelfix/pectin (from 1:1 to 4:1 possible).

Option 2:
Set the switch from fruit to jam sugar or Gelfix/pectin. Move the jam sugar to the desired amount (or so that you achieve the desired amount of fruit). If you now increase the liquid, the amount of fruit will be reduced and the jam will be less sweet.

Option 3:
If the switch is set to fruit, you can add water in addition to the fruit, which will also make the jam less sweet. However, this will increase the total amount.

Is there anything I need to consider regarding the ratio of fruit to added liquid?

Remember the old rule: the more liquid the mixture, the more gelling agent is needed.

How do I know what size pot I need?

First enter your fruit, jam sugar or Gelfix/pectin, etc., then the app will display at the top the total amount of jam you will get finally.
Since one gram of the mixture corresponds to one milliliter, you can simply round up the total amount. For example, you will need a 3-liter pot for 2500 grams of jam or a 1-liter pot for 800 grams of jam. Make sure you have enough space to stir the jam comfortably, so it's better to use the next size up rather than a pot that is too small.

How much time do I need to plan for making my own jam?

Once the fruit has been washed and prepared, you can simply bring the mixture to a boil. Most fruits will be soft after about 10 to 15 minutes, at which point you can add the jam sugar or, if you are using Gelfix/pectin, the Gelfix/pectin and sugar. It is important to ensure that the sugar and jam sugar or Gelfix/pectin dissolve completely. Everything should boil for another three minutes. It is important to stir constantly.

Depending on the fruit, it takes about 15 to 20 minutes to cook the jam. However, plan extra time for preparing the fruit and filling the jars.

How do I know when my jam has set and is ready to be put into jars?

To do this, place a small dollop of the cooked jam on a cold spoon or plate. Wait a moment, then tap it with your finger. If the jam becomes set, it will be thick and sticky.

Is there anything I need to bear in mind when making jam if I want to add spices or herbs?

No. Neither herbs nor spices contain enough liquid for this to be important for setting.




Fast and clean filling with the jam funnel

If you make jam frequently, it will probably help to use a funnel so that you can pour the jam into the jar quickly and cleanly.
The opening of jam funnels is wider so that even larger pieces of fruit can pass through. This prevents anything from getting stuck.

Save money by reusing jars

You don't need to buy expensive new jars to make delicious jam; any jars that previously contained food (jam, preserved fruit, etc.) are suitable.
Make sure that the jar has a lid that can be pressed up and down when open (so-called twist-off jars). Clean the empty jar and remove the label. Before removing the label, note the specified filling quantity, which you can set under “Jar size” in the app.

Preserving jam

Before pouring the jam into clean jars, boil the jars briefly.
To do this, pour boiling water over the lids and jars, wait a moment, then pour out the water and place the jars on a clean dish towel. Be careful that the jars and lids do not get dirty again.
If it suits your taste, add a little citric acid. This also extends the shelf life, but is not absolutely necessary.
If the jars are very clean, this is usually enough to ensure that the jam will still taste delicious even after a year.

Organize your pantry

Label your jars with the date you made the delicious jam and the fruit or flavor so that you can easily tell them apart.
You can do this in a creative way, so that your pantry looks nice and it's even more fun to take a jar out of the cupboard.
Alternatively, you can also buy simple template labels—they are also available for printers.




The information contained herein is based on years of experience in jam making. The content has been compiled to the best of our knowledge and belief and has been checked against information provided by leading manufacturers (Dr. Oetker, RUF, Diamand, Sweet Family, etc.).

The content of the app is intended solely to assist you in calculating the amount of jam sugar or pectin and the number of jars required to make homemade jam. All content is NOT approved for commercial, business, consulting, academic, professional, legally binding, or similar purposes, nor is it intended for such purposes.

We are constantly working to improve the app. Nevertheless, calculations may be incorrect and, in the worst case, may even contain recommendations that are hazardous to health.
We are only liable for the intended use and exclusively within the scope of the App Store's “LICENSED APPLICATION END USER LICENSE AGREEMENT” (EULA) and legal provisions.
Furthermore, as the developer of this app, we accept no liability, in particular for the accuracy, completeness, and timeliness of the information and any resulting damage, consequential damage, or other disadvantages.
Before using a jam sugar, pectin or fruit, always check for intolerances or allergies.




The development of this app took a long time and is based on many years of experience. It would be great if you could take a moment to leave a few stars in the App Store. Thank you.

If you have any questions, suggestions, or criticism regarding this app, please send an email to: iolanovateam@gmail.com



Jam Cooking Calculator Privacy Policy


No personal data is processed when using the Jam Cooking Calculator-App. You can use the Jam Cooking Calculator App without providing your personal data.

You can always reach out to us if you have any questions about data protection law or about your rights as a data subject under: iolanovateam@gmail.com

The Jam Cooking Calculator-App is subject to the European Data Protection Guidelines (GDPR), https://commission.europa.eu/law/law-topic/data-protection/legal-framework-eu-data-protection_en

This data protection policy is currently valid and was last amended as of August 2025. Due to further development of our App or due to changed legal or regulatory requirements it might get necessary to amend the Jam Cooking Calculator-App data protection policy.