Looking for MOD which calculates the amount of visible resources

[Qeeet]

Basically, I need to know how many resources I have on the map to decide which modules to use so that all resources to be used up evenly in order to fulfil my OCD.

[Qon]

https://mods.factorio.com/mod/ResourceLabelsContinued might help?
You need to use the hotkey to activate label generation.

[mmmPI]

There is this one too https://mods.factorio.com/mods/Narc/YARM

I didn't know about the other one i did those label manually during long train travel

[Qeeet]

Thank to you all for the answers. But I was looking for a mod which provides just with information about how many resources there are on the visible map.

There is this one too https://mods.factorio.com/mods/Narc/YARM

I didn't know about the other one i did those label manually during long train travel

I used this mode and manually selected ore mines and summed up in calculator

[Qon]

But I was looking for a mod which provides just with information about how many resources there are on the visible map.

Define visible map?
If you mean just the resources that you can see on the map with the current zoom and position in map view, that is impossible.

A selection tool like https://mods.factorio.com/mod/ore-eraser (save, use, write down/memorise counts and then load the save) can be used from map view (if you zoom in enough) and used to count resources. It will sum it up for you automatically. And it gives you both the number of tiles and total resources that were deleted.

Ore Eraser crashes if you select more types than the default resource type count though. But if don't have more than that it should work.