Munich to Rothenburg Day Trip

You probably mean the transfers in Treuchtlingen or Ansbach and Steinach bei Rothenburg. Well, all those are small stations, where a transfer time of 3 to 5 min is quite normal. Just collect your stuff before the train stops and be at the door when it does. If you go through Nürnberg you need a bit more time since that station is large and trains to Ansbach usually leave from the southernmost tracks (#20 to 22). Anyway, if the DB website offers you an connections with short transfers it assumes that you can make it without running.

A bit of a warning: We were doing this in 2015. We were warned that the train would split at some point. It was not clear to us which part of the train to be on. The announcements were in German and no translation was offered. I have a modest command of German, and asked which train to get on. We picked the wrong one, and went the wrong way. So, get very very clear directions, or possibly consider Flixbus instead.

Thank you for your response. It eases our mind and encourages us to give it a try and not miss Rothenburg.

Paul,
Just read your response. At what point in your route did the train split and what kind of warning were you given? Thank you for the valuable info.

It's been 3 years, and i can't remember exactly. We were told it was going to happen. Somehow we got confused. Although I have a little German, listening to complicated instructions on a train intercom is not my linguistic sweet spot. That's why I suggest a bus.

At what point in your route did the train split

The only conceivable point is Augsburg, where some regional trains arriving from Munich are split into a segment going to Ulm and another going to Treuchtlingen. You don't need to understand German: just read the overhead indicator in the train. If it says "Ulm" (or sometimes "Dinkelscherben") you will have move in Augsburg into the other segment of the train bound for Treuchtlingen. There is plenty of time to do that.

That's why I suggest a bus.

I doubt very much that you would find a direct bus from Munich to Rothenburg. You can check that at busliniensuche.de

Lubitsch has offered the best advice thus far IMO. Take Regensburg for example. Unlike Rothenburg it's not merely a place for tourists, but also a thriving historic city with UNESCO World Heritage status, a university town, and a generally fun place with lots to see and do.

https://www.tripadvisor.com/Attractions-g187312-Activities-Regensburg_Upper_Palatinate_Bavaria.html
https://www.regensburg.de/unesco-world-heritage/impressions

DIRECT regional express trains from Munich get there and back in just 3 hours (€31 round trip for two on a Bayern Ticket day pass.)

You can use the Bayern Ticket to Rothenburg and back too, but the regional trains will mean 6.5 - 7+ hours of train travel that day. The fastest trains don't get you there much faster - they cut the time down only marginally to 6-6.5 hours - and you still have to take 3 different trains and sometimes a bus depending on when you travel there. Rick Steves indeed recommends Rothenburg but it seems a bit like a Rothenburg fetish of sorts - even he admits that "Rothenburg is well on its way to becoming a medieval theme park."

Another option would be staying over night in Rothenburg. We enjoyed our overnight there. We chose to rent a car from Munich (we dropped it in Dresden). One reason was the time it would take by train with the many transfers required to get to Rothenburg.

"We chose to rent a car from Munich (we dropped it in Dresden). One reason was the time it would take by train with the many transfers required to get to Rothenburg."

The car makes sense perhaps if you have additional driving goals beyond R'burg, but a day trip from Munich is a different matter. Driving to Rothenburg (not that I'm recommending Rothenburg) from Munich will save you only about 30 minutes one way over the train ride. You of course would need to get to the rental outlet for the pick-up process and drop it off later that day or the next morning as well (which would require some unknown quantity of time.) Gas alone would be about €40-45 on top of rental fees, insurance, parking etc. If indeed you must go there, I think the train (Bayern Ticket, €31 round trip) would be the more reasonable alternative.

Thank you for the advise. We are rethinking our plans.

All this information is making me re-think Rothenberg too. Interested in knowing if anyone here would recommend Regensberg over Nuremberg, or should I try to do both of those on separate days?

I really love Rothenburg, but no way would I do it as a day trip from Munich. Either spend the night or take one of Lubitsch's recommendations for a town closer to Munich.

Tyger. I worked in Nuremberg (Nürnberg) and loved the city, but we still think that Regensburg was better tourist stop. We have visited both several times in recent years with great pleasure. You can not go far wrong.