FRA overnight connection what would you recommend for hotel

I fly through FRA regularly and have stayed at many airport hotels there. There are many to choose from, but they do book up and get more expensive, so book as early as you can.

If it's in your budget, my preference is to stay in the airport where there is a Marriott/Sheraton closer to the airport and a Hilton and a Hilton Garden Inn right above the long-distance train station attached to the airport. Both are 5-10 indoor, easy walk to the check in area. These are typically the most expensive option, because of the convenience. Particularly for a 10am flight, I would try to get one of these.

One S-bahn (local train) stop away from the airport is the Gateway Gardens area that has a tons of hotels of every class. I like b'mine. I don't think many of these hotels have shuttle busses because of the convenience of the S-bahn. But you'll need to figure out the system and buy a ticket, or Uber there. This area is not a place to explore Germany, only because it's really only places to sleep sandwiched into office buildings. There is a local grocery store in this area (Rewe) so you can get provisions, but you'd probably have to have your meal at the hotel or in the airport

Finally, when prices are unexplainably high, I've often stayed at the Hey Lou, which is further from the airport. But a shuttle bus to and from the airport is included in the price. There is absolutely no where to eat in this area except for the hotel. The hotel is a lower class, but the prices is usually very reasonable, and it's clean and safe.

Have in mind that FRA airport will have started to operate new Terminal 3. More info:
https://community.ricksteves.com/travel-forum/transportation/frankfurt-terminal-3-opening-planned-for-april-2026

This might influence your ways at the airport, different to what you see today.

I stayed at the Holiday Inn, one stop away from the airport at Gateway Gardens and about a 5 minute walk from the S Bahn Station. Very large room, clean and comfortable.

We have stayed at the Hilton Garden inn a few times. It isn’t terribly expensive but so worth the convenience to just walk off the train and the next morning into the airport just minutes away. Friendly people. Several dining options are in the Squaire Building that the hotel is located in. We just grab a sandwich and that’s fine for us but many people prefer more of a regular meal. I have finally. convinced myself that a trip must end sometime, so no more dragging into town for one last hurrah. A sandwich, a shower, and an easy early night. Safe travels.

Travel between FRA airport and downtown Frankfurt is extremely convenient and inexpensive. Multiple rail/bahn options are available taking less than twenty minutes. The Frankfurt Central (main train station) area is filled with quite a few hotels, restaurants, and even a vibrant night life that are easily accessible by walking. The rail service is located in terminal 1. You absolutely do not need to use a taxi unless cumbersome luggage, mobility, etc are variables.

Stay in the city. It is light out until quite late and the downtown area around the river and the Römerberg are beautiful when they light up or at sunset. Get a hotel by the Hauptwache and then you can ride the S-8 or S-9 directly to the airport. Train every 15 min. and it only takes 15 min. to get there.
Try Flemings City by Eschenheimer Tor, or Moxy. Both are a decent price.

I have twice stayed at the Hilton Garden Inn at FRA. The first time was fine, the second time I had lots of mechanical issues in two different rooms.

b‘mine FRA Airport Hotel is my favorite place to stay near the Airport. Often, the prices are not so expensive. I always booked a room with airport view. I like the restaurant. It has a great view to the airport and a great terrasse. Once I walked from the hotel to the airport. I guess, it took 25 minutes. Not far, but the way was not so nice for walking. Would take a taxi or uber.