- The buildings are all (or mostly) Art Deco style.
- Men's fashion seems to be 1930s-40s-era with fedoras being quite popular, though men's fashion tends to change slowly, while women's fashion is more 1940-50s-era.
- Multiple rigid airships are seen throughout the series, though the practice of building large rigid airships (zeppelins) went out of favor after the crash of the Hindenburg.
- Computers, VCR and video games are common, yet television broadcasts are in black and white.
- Nobody objects to women having careers or Lucius Fox, a black man, being in a prominent position at Wayne Enterprises.
- Uniforms are 1960s-era and SWAT teams exist, but weapons are 1920s-70s, with M1921 or M1928 Thompsons and 100 round drum magazines being very common while police — or at least patrol officers — carry revolvers and shotguns for the most part.
- Cars are 1930s-40s, Liebherr-type cranes exist, helicopters are from the 1980s.
- Charlie Collins' driver's license◊ was issued September 25, 1991, expires March 17, 1995 and lists his date of birth as March 17, 1946.
- A photo from Thomas Wayne's graduation, which Bruce says happened 40 years prior, is dated 1908.
- The Gotham State University football team wears leather helmets, but plays in a domed stadium.
- In the Direct to Video, Subzero, the music Dick and Barbara listen to is almost exclusively 40's-ish jazz with some doo-wop thrown in.
- The tech, fashions and architecture seem to take quite a jump forward by The New Batman Adventures, despite it taking place only a few years after the original run.
- By the time you get to the flashbacks in Return of the Joker, integrating DNA into microchips is possible.
Anachronism Stew / Batman: The Animated Series
Intentionally invoked by the creators to make when the series takes place ambiguous, largely as a nod to Batman's invention in The Thirties.