So lets begin with the Nids.
In the
BRB there is a passage on the Hive Fleets (sub box page 237) which states there have been 9 distinct Hive Fleets in the Galaxy thusfar with "millions" of ships comprised of "mililons" of creatures ready for invasion.
Taking the lowend numbes first that would give us:
9 x 2,000,000 (2 million) x 2,000,000 (2 million)
Im taking 2 million as the very lowest end as the word "millions" implies more than one.
Hence, that totals:
3.6 to the power of 13.
That equals 360 trillion.
Next we take the extreme upper end. Since millions implies more than 1, the Nid fleets could reach a cap of 999,999,999 (or nine hundred and ninety nine million). So could the creatures onboard (as per the passge quoted).
There are 9 distinct fleets.
Hence
9 x 999,999,999, x 999,999,999
= 9 to the power of 18 which is called 9 quintillion
afaik (9,000,000,000,000,000,000).
So thats the known Nids upper and ower ends. Obviously the other fleets int he Galactic Void and elsewhere could be even larger than this (or smaller too) but there is no hard evidence on them at all from what I can see.
Next is Humanity - I havent tried to do the Imperial Guard as the numbers are hard to pin down.
It is quoted in the
BRB (page 170) that Humanity numbers around 1 million worlds. It also states this could be more or less due to the inherent inefficencies of tracking all the worlds so lets take the 1mil mark as a good base.
This is where things get less clear
imo though.
Wiki quotes the
IoM as having 32,380 Hive worlds. Each world can have 5-20 Hives with populations ranging fro 10 to 100 billion.
http://warhammer40k.wikia.com/wiki/Planets
Personally Im unsure of where these numbers came from but lets try them out to see.
Lets start with the lower end for Hive worlds.
32,380 x 5 (hives) x 10,000,000,000 (10 billion)
= 1.6 to the power of 15 or 1.6,000,000,000,000,000)
or 1.6 quadrillion in short hand.
Things get difficult here however as there are no hard numbers for the other types of
IoM worlds, civilised, fuedal, forge, death, agri, death etc.
Sticking with the low end figures fuedal worlds are stated to have a min population of about 10,000,000.
So taking 1,000,000,000 (total worlds) minus 32,380 (the Hives) leaves us with 967,620 worlds.
967,620 x 10,000,000 = 9.6 to the power of 12 or 9.6,000,000,000,000
or 9.6 trillion (note not even a patch on the Nid lowend numbers).
High end
IoM then:
High end Hive
32,380 x 20 (hives per world) x 100,000,000,000 (100 billion)
= 6.5 to the power of 15 or 6.5,000,000,000,000,000
or 6.5 quadrillion
Taking the remaining 967,620 worlds and maxing all of them below a Hive worlds cap 99 billion (acknowledged this is wacky and dosent fit with feral, fuedal worlds) gives:
967,620 x 99,000,000,000
= 9.57 to the power of 16 or 950,000,000,000,000,000
or 950 quadrillion
+ Hives = 956 quadrillion.
Note still nowhere near the Nid upper levels.
Finally we can do an extreme
IoM and say 1 millio worlds by the Hive cap of 100 billion
1 million x 100 billion=
1 to the power of 17
or 100,000,000,000,000,000
100 quadrillion.
About one tenth of the Nid population.
