[kypfer]

On Ilford's ID-11 packaging they quote :- "ID-11 powder in dry conditions will keep indefinitely"
I'd like to confirm this appears to be true
A 1 litre pack of ID-11 that had been stored "under the bed" for around 20 years was made up last December and is about to be discarded after successfully processing the recommended 10 36 exposure 35mm films, though I might try a couple of tests with some also very outdated roll film just to see how far it can be pushed and/or how badly the roll film has deteriorated.
I've been spending some time assessing the performance of a few old film cameras over the last three months and took the opportunity to test some old film that had also been stored under the bed, anticipating not very much in the way of results, but at least I'd know if the cameras and lenses worked!
Nevertheless, 20 year old Paterson Acupan 200, Phototech 100 and Ilford SFX have all proven to be perfectly useable, albeit with slight background fog, but Kodak TMax P3200 had deteriorated to virtually useless.
The cameras, a '64 Spotmatic, an Exa 1a of similar age, a Chinon CE-4, a Miranda Fv and my "one owner from new" *ist have all proved perfectly reliable, used, where necessary, in conjunction with my Weston Master V light meter.
The waist-level viewfinders on the Exa and especially the Miranda proved to be a "refreshing" experience
Next up … a pack of Kodak D-76 of similar age and some Kodak HIE

[rvandenbrink]

Can confirm, used some ID-11 form high school a few years ago (I was ~55 at the time)
Once mixed of course it’s a different story

[tuco]

D-23 is just two dry chemicals, Metol and Sodium Sulfite, that you mix at the time of use (single shot). And it will also keep a very long time unmixed. It is a good economical choice for people who develop film infrequently. Development times and results are nearly the same as D-76.

[StiffLegged]

D76/ID-11 is just four dry chemicals, or was in my day. If kept dry and cool I’d expect it to keep a long time. I used to make it up from the ingredients myself.