The spatiotemporal scale used to calculate extreme precipitation intensities can introduce strong biases when investigating their physical origin, impacts, and sensitivity to climate. Besides, the contribution of Mesoscale Convective Systems (MCSs) to tropical precipitation extremes remains loosely quantified on various scales, in particular on kilometer scales. Here we analyze the co-occurrence of extreme precipitation at convective and mesoscale levels to compare their properties in terms of precipitation morphology and regional predominance. Using a storm tracking algorithm, we contrast the occurrence and rain statistics for various types of convective systems across ten global storm-resolving models and one geostationary satellite product. We find a large statistical independence between rain extremes on these two scales, as they occur in distinct regions. Heavy km-scale events occur mostly over continents, over margins of convective zones, 40\% of which are produced by MCSs in observations. Their intensity is independent from the area of rain features. Conversely, heavy mesoscale rain intensities scale with the area of rain features, occur more frequently over oceans and a third of these events are produced by MCSs. More generally, a continuum between these extremes emerges from the wider variety of convective systems, quantified here as deep, very-deep and mesoscale convective systems. Compared to observations, models consistently underestimate the precipitating surface and show high variability in the contribution of convective systems to precipitation extremes at each scale. This diagnostic can serve as an evaluation criterion for the ability of GSRMs to represent how individual convective systems produce realistic heavy rain distributions.