The conversion, both directions
1 cal ≈ 4.2 kJ
To go from calories to kilojoules, multiply by 4.2
1 kJ ≈ 0.24 cal
To go from kilojoules to calories, divide by 4.2
Food labels are built around a reference day, and the reference differs by country. A US Nutrition Facts label uses 2,000 calories. An Australian label, which is what these guides were written against, uses 8,700 kJ, which works out to about 2,080 calories. Either way it is a reference point for designing the label, not a target handed to you personally.