How many R2 droid units were there according to canon?

Question

We know that most Star Wars droids were designated using 4 letters of High Galactic alphabet (which is basically Latin so base 36 including numbers).

Then, the upper bounds on named R2 units would seem to be be 36^2=1296 even assuming random 2 letters at the end, and 26*10=260 assuming the typical naming scheme of Letter+Digit.

Is there any notion in canon of just how many R2- units were ever produced?

Wikia (unsourced) says:

he R2-series astromech droid was a model of astromech droid produced by Industrial Automaton, boasting a level of success that was never equaled in Industrial Automaton's long history. A combination of excellent design, high-quality marketing, and good timing made this astromech droid one of the most sought after droids in history, and one of the few vintage astromech series still in active production decades after it was first designed, including the prototype R2-0. The line was so successful that the Galactic Empire took credit for the design.

Given the size of the Galaxy (millions? of inhabited planets, gazillions of beings), a production run of 260 - or even 1296 - seems to square very poorly with "one of the most popular astromeh droids in history with multi-decade production run".

Is there ever a canon explanation (ANY canon) for this?

• Were there tons of non-designated R2 units?
• Were later models designated differently, perhaps not limited to R2-$L$D scheme?
• Were there really only 260 or 1296 R2 units in the entire galaxy? Some other explanation?
• Was the assumption that such designation was a unique proper name - implied by the use of ArtooDeetoo as a proper name in the movie as well as similar references to all other droids - wrong and such designations were in fact reused for multiple droid units?

Answer 1

Found the canonical answer.

Apparently, there indeed were tons (at least could have been tons) of R2 units to match the size of the Galaxy, because the 4-letter naming scheme was merely a human convention, out of laziness, to pick something to call their droid. In reality, a droid name was a long complicated GUID-like string, e.g. "R5-X41238-G8-R3-3124-D2", which is shortened by its owners (the starship of Queen Amidala crew) to "G8-R3", which was an astromech droid).

Source: Pablo Hidalgo (Internet Content Provider for starwars.com) Q&A in Star Wars Insider #58 (Page 97)

Answer 2

The R2-Series Astromech Droid wookieepedia entry you link also lists a few example units.

• R2-D2
• R2-Q8
• R2-T7
• R2-Z13
• R2-Q5
• R2-R7
• R2-KT

You'll note that R2-Z13 sort of breaks the supposed R2-$L$D naming scheme with a letter and two digits. While this doesn't provide a concrete answer, it does demonstrate that the naming conventions are not quite as limited as you originally believed.

Wookieepedia also had a larger list of R2 units. (note: archived version as page is now gone)

Again, you'll find more units with model numbers which break that scheme - including P3-NUT and 6R-OWL. The possible model numbers suddenly increases by incredible numbers.

Answer 3

While I haven't found any canon detailing the number of models, simple logic would tell us that it is impossible for there to be only 260 or 1296 R2 units, given the following facts:

• Most hyperspace capable star fighters we know of required an R2 or other Astromech unit, including those used by the Jedi, those used by Naboo, and those used by the Rebel Alliance.
• Astromech droids, and specifically R2 units are seen being used on star ships for maintenance tasks, including 3 or 4 on the queen's ship alone. As I recall, I think we also see one or two working on one or both of the death stars

Given just those two facts alone there must, by any logical standard, be far more than even 1296 Astromech droids. It's probably more likely that there are hundreds of thousands, if not millions or more R2 units out across the galaxy.

I think what is more likely, though I know of no canon to support it, is that given the nature of humans to give things short nicknames, R2-D2 is just the "short" version of a much longer identifier. It's probably something like R2-D23AF434DDOR219989, etc

Answer 4

There are canonical and Extended Universe R2-series units with 1,2, and 3 characters after the dash... and even a couple with 4.

Assuming a latin alpha-numeric system, you get effectively 37*37*36 (since you can't have 3 blanks), less 36*36 for blank-Char and Char-Blank being identical in end results. So, 47,988 without the rare 4th character.

If we take some of the EU examples, like R2-D609, we now have another multiplier of 37... 37*37*37*36-36*36*36=1776852.

Roughly 1.77 million, again reducing for blank equivalence.

Answer 5

If you are asking how many "types", you are right about 1296. But if you are asking the total numbers, by thinking of r2d2 being both a co-pilot astromech and a maintenance droid, 1 droid per fighter and many droids per capital ships, there would be more than tens-of-thousands maybe millions of them.

If you count the blackmarketting, there would be thousands with same name. (Anakin rebuilt c3po but could have build r2d2 easily i think )