Wash the peaches thoroughly. Peel the skin, remove the pit, and chop them into small pieces.

In a large saucepan over medium heat, combine the chopped peaches and lemon juice. Stir occasionally until the peaches start to break down and release their natural juices (about 5–7 minutes).

Once the peaches are soft, mix the granulated sugar and fruit pectin into the pot. Stir well to ensure the pectin is fully dissolved.

Increase the heat to high and bring the mixture to a rolling boil, stirring frequently. Once it reaches a full boil, let it boil for 1–2 minutes until the mixture thickens slightly.

Remove the pan from heat and carefully ladle the hot jam into clean, sterilized jars, leaving about 1/4 inch of space at the top. Seal the jars immediately.

Allow the jars to cool at room temperature. Once cooled, store them in the refrigerator or pantry for up to a year.