Big mining drill to belt ratio?

[A boy named Sue]

How many big mining drills does it take to saturate a belt? Lets say red. Is it really just 30/2.5? Or are there other considerations?

[PunCrathod]

The number depends on a bunch of different researches that it is more practical to just test it yourself.

[Chindraba]

Originally posted by PunCrathod:

The number depends on a bunch of different researches that it is more practical to just test it yourself.

And keep testing it as you do more researches and add modules and beacons and quality. It will only change until the game is closed.

[Fel]

The base mining speed is 2.5, or 5 times the electric mining drills.

Without any bonus from researches at all (no stacking and no productivity) and on basic ores (with mining time of 1), they output 2.5 ores per second, so 6 per side fill a yellow belt (or 12 for red belts).
On top of the mining productivity (which increases the production for all mining drills), they also gain the ability to ouput stacks on belts (which increases the throughput of the belts) from research, so the specific number of drills per belt can change drastically depending on your current technologies.