Train travel in Germany

You would have to total up the costs of where you plan to go to see if it exceeds or is less than the cost of the 5 consecutive day pass
which is 216 euros 2nd class 293 euros 1st class

https://www.bahn.com/en/view/offers/passes/german-rail-pass-conditions.shtml?dbkanal_007=L04_S02_D002_KIN0060_GERMAN-RAIL-KONDITIONEN_LZ01

Depends where you are going, how far from Frankfurt. There is not one pass for 5 days.
For within and around Frankfurt am Main, you can get a "Tageskarte" (day ticket) for the local transport area.
For slightly further, there is a "Länder Ticket" for the whole state.
Or you can buy cheap advance-purchase tickets for the ICE high speed trains.

If you are making out-and-back day-trips, I'd be extremely surprised if a rail pass saved money. Germany seems to have very good deals on regional tickets, and I think the second person often pays less than the first when two travel together.

We have several people on the forum who are experts on German rail travel. If you know which cities you will travel to (or even just some of them), post a list. I'll bet you get a detailed response about the best ticket to buy in each case.

Here's the Deutsche Bahn website, where you can do some preliminary investigation. I don't know whether the special regional deals will show up there, however.

"We will be based in Frankfurt for 5 days and travel to other towns by rail."

Which other towns? In addition to the Frankfurt markets, there are Christmas markets within fairly easy striking distance, say an hour or less. But you won't find those ticket prices at the German Railways site - the local transit authority (RMV) handles those. Here are those prices so you needn't fuss looking them up. These prices are for day passes to cover two adults between Frankfurt and the town in question.

Mainz Market... RMV group day pass, €28
Rüdesheim Market... RMV group day pass or Hessenticket day pass, €35
Darmstadt Market: RMV group day pass, €28

You would just buy these day passes at the station from a ticket machine on the day of travel.

So day trips will be very inexpensive if you're doing the area near Frankfurt.

If you are planning long-distance train rides, you can likely find fares at the DB site, and a rail pass may or may not be more worthwhile.

You would have to total up the costs of where you plan to go to see if it exceeds or is less than the
cost of the 5 consecutive day pass which is 216 euros 2nd class

That's 216 euro per person. A twin pass, for 2 people always together, is 324 euro, or about 65 euro per day for the two of you. A lot depends on where you are going.

If you are going to larger cities and want to use long distance trains, saver fares for two people, round trip, will probably cost more than 65 euro per day. Advantage rail pass.

On the other hand, if where you are going uses only regional trains, passes will cover all day travel (round trip) for two people for less than 65 euro. Advantage point-point tickets.

Cheapest? Not the rail pass. Think about what you both want to do and buy advanced-purchase DB tickets online in advance.

"Think about what you both want to do and buy advanced-purchase DB tickets online in advance."

What's cheapest really depends on what it is they want to do.

The current (promotional) price for the 5-day consecutive German Rail twin pass (covers 2 adults) in 2nd class is €292 or about €58 per couple per day.

https://www.bahn.com/en/view/mdb/bahnintern/international/partnerbilder/pdf_2017/mdb_255495_grppromo102017_pricelist_bahncom.pdf

Advance-sale tickets can offer some savings. Want a day trip to the Nuremberg Christkindlmarkt? For sample date 12/15, the cheapest price I see for two for the 2-hr. trip is €59.80 leaving Frankfurt 8:54. Returning from N'berg at 21:00, the same price is possible. That's about €120 total for the day trip for a couple, and that's if you buy those tickets NOW - prices rise as tickets sell.

If you were doing Nuremberg one day and the 3 closer towns I mentioned on 3 separate other days, you'd spend about €210 altogether if you travel on the trains I indicated. Price advantage to individual tickets. But that's with only one long-distance trip, and AFAIK it's based on a trip price available only on that day and at those travel hours. Most journeys for two to Nuremberg on that date are priced from €80-90 one way. Even one additional long-distance day trip is likely to put you over that €292 rail pass threshold; travel on a different date / different hour than I used in the example may cost much more, and prices are certain to rise over time.

Price isn't the only advantage of course. Maybe you don't want to have a pre-ordained schedule. Maybe you just want one pass that lets you hop on/off as you please, or to make additional side trips (at no charge,) or to travel without fussing with ticket machines and credit cards. There is often value to these advantages, value that might be worth additional costs (if any) that a rail pass might come with.

Interesting pricing through DB for an upcoming trip, train travel from Amsterdam with stops at St. Goar, Nuremberg, Hall in Tirol (Austria), then down to Verona in Italy.

I checked out routes/fares at end of February 2018 travel times (although it might be later than that), and saw that the cheapest advance 2nd class tickets Amsterdam/St. Goar are 44,90 pp, St. Goar/Nuremberg 55,90. But Nuremberg/Hall in Tirol tickets are only 29,90, and Hall in Tirol/Verona 29,00.

In the grand scheme of things, still an overall great value, but it appears the German legs are consistently pricier, quite bit more than that if not booked far ahead. I'm used to dirt-cheap with Trenitalia, even though the service and timeliness might leave a little to be desired!

the cheapest advance 2nd class tickets Amsterdam/St. Goar are 44,90 pp, St. Goar/Nuremberg 55,90. But Nuremberg/Hall in Tirol tickets are only 29,90, and Hall in Tirol/Verona 29,00.

That's easy to understand. Amsterdam - Cologne and Frankfurt - Nuremberg are very busy connections. In contrast, there is an oversupply of ICE's between Nuremberg and Munich, because here the ICE lines from the north and west bundle. At many times of the day there are four ICE's per hour - too many to keep prices up.

As others have noted train prices vary by destination. I would further make the case that it might be best to think of staying close to Frankfurt most of the time. Markets are pretty much the same in any moderate to large city. The reason to travel is to sight-see and there is plenty of that in any area of Germany. Jo that lives in Frankfurt often posts a list of possible markets in small cities in the local area. Here is a trip report by her for last year.

https://community.ricksteves.com/travel-forum/trip-reports/german-christmas-markets-2016

You can make on the spot decisions to visit towns in the vicinity like Mainz and Darmstadt that Russ mentioned. We always enjoy Würzburg. Even if these are outside the local and state (Land) networks they can be reached by a Quer-Durchs-Land-Ticket for 52 Euros roundtrip.

https://www.bahn.com/en/view/offers/regional/day-ticket-for-germany.shtml

There are bargains on long-distance trains but then you are committed to a specific time and place.

There are so many good choices in and around Frankfurt that I would be reluctant to spend too much time any day traveling.