Christmas markets

Nuremberg and Stuttgart are two of the best. There are also a couple of good ones in suburban Stuttgart

My favorites are Stuttgart, Esslingen, Marburg, Mainz, Idstein, Limburg, Regensburg, Seligenstadt, Büdingen, Gelnhausen, and yes, Frankfurt. Hoping to go to Erfurt, Cologne, Dusseldorf, Worms, Speyer and Berlin this year.
Depends on what you want. Small town quaint or huge with crowds, towns with something else to do (like museums) Many large cities have multiple markets, like Berlin or Cologne.
Looking for atmosphere or hand made items or just food, drink and fun?

Bremen should be on the list for sure!

Dresden is one of our favorites, but the city of Dresden is also a favorite. Honesty, we have been to Markets dating back years and my conclusion is if you love Christmas, you'll love the markets. Some better than others but all of them just the same.

https://community.ricksteves.com/travel-forum/trip-reports/christmas-markets-switzerland-france-germany-2019

Perhaps my 2019 xmas markets Trip Report above will have some helpful suggestions.
It's a magical trip, for sure!

Safe travels.

I don't understand how Nuremberg always gets on the list of best markets. I really didn't like it at all.

On the other hand, the markets in Koln were FANTASTIC!! There was such a variety from traditional to adult-themed and everything in between.

Looking forward to adding Munich and Heidelberg to my list of German market visits this winter.

If you are going to the Nuremberg Market (really big and glitzy) anyway consider having an evening adventure and take the S-Bahn north to the little town of Furth where their local market is really reasonably sized and not glitzy and is filled with Germans enjoying the Gluhwein and local delicacies. Depends if you are going for the shopping or the ambiance. Note: The first railway in Germany connected Nuremberg and Furth. It was a long way then.

Dresden (several markets), Görlitz, Schwarzenberg, Annaberg-Buchholz, Freiberg, the town of Seiffen where so many wooden Christmas items are manufactured and you can visit the small workshops ...

Nuremberg and Trier. The first is huge, the latter is smaller but when you turn the corner at night and see the Cathedral lit up with booths in front of it.....oh my! And for small town markets I lived Queidersbach, near Ramstein. It's been over a decade so it might be bigger but part of it was inside so you could warm up, and they had German Christmas carolers. It was only on 1 weekend though.

I would agree that Nuremburg should be on the list, but it is large and does tend to get crowded. We really liked Regensberg. It consisted of two smaller markets. One more modern and one that had a Medieval feel to it. It was easy to walk around and enjoy. Have also been to Bamberg and Bayreuth and enjoyed those. Like it was said...If you like Christmas and are in the mood, you'll like them all!