Understanding how much crops like wheat, rice, and maize can potentially yield is crucial for helping farmers improve their harvests. By analyzing 64 recent studies, it was found that the global yield potential for wheat is 6.7 tons per hectare, for rice it's 8.1 tons per hectare, and for maize it's 11.2 tons per hectare. However, farmers are only achieving around 60% of this potential yield on average. Using crop models to estimate yield potential was shown to be effective. By implementing better management practices, such as integrated soil-crop systems, farmers can reduce this yield gap and increase their harvests. There is still a lot of room for improvement in increasing grain yield for these major cereal crops.