In this context, ”berth” apparently means a reservation in a couchette car while ”sleeper” means a reservation in a sleeping car. Read https://seat61.com for information on the difference between couchette and sleeping car.

Berth means here Couchette (“Hard sleeper”) it´s like a Hostel and you sleep with up to 5 foreigners in one compartment.

Sleepers (“Soft Sleeper”) offer max. 3pers compartments (sometimes even a small breakfast) and is a bit more expensive. Sleepers have often a wash basin in the cabin and in case of Deluxe (Austrian Rail) or Excelsior (Trenitalia) even a private WC & Shower next to the compartment.

If you let me know which train you are trying to reserve i may can share some example pictures from Vagonweb.cz

But really-this must be a grand mistake/error. You will NOT get any berth/sleeper/bunk/bed for just 4 €-even in UKrayna before the war it cost more.

A couchette tipically in West-EUR cost around 20-25€ and a real sleeper at least 30-40. SNCF on their newly installed overnighters (as I just bought one) charges 21,50.

They say sleepers replace a hotel-but thats nonsense, if you really compare what you get its even less as a bed in a hoStel=multi bed rooms. hoStels will also give you much more: kitchen use, a real bath/shower, common room, often free cf/T etc. and their beds will be much more space around.

Fees for just a seat will indeed be from 3-6/7€, higher if it also includes superfast hi-speed sectors.

Ah indeed. I didn’t even pay attention to that. The €92 for a “berth” in a 4 person compartment again sounds way too expensive, if it means one reservation in a shared 4 person couchette. Unless it perhaps means single occupancy? Etc. The whole table is weird.

@sophie.a , where is this table from? What website? Is perhaps some automatic translation involved? 

Hello, 

I looked on https://www.interrail.eu/en/book-reservations#/ to get an idea of the prices. But as you said it sounds really fishy …. 

This is what I searched for :

ZURICH MAIN STATION (SWITZERLAND) to WIEN (AUSTRIA)

Mon 08/08 at 18:00

And the whole options I get are : 

Should I not book on the interrail website but rather on the website of each train company ?

Hello, 

I looked on https://www.interrail.eu/en/book-reservations#/ to get an idea of the prices. But as you said it sounds really fishy …. 

This is what I searched for :

ZURICH MAIN STATION (SWITZERLAND) to WIEN (AUSTRIA)

Mon 08/08 at 18:00

And the whole options I get are : 

Should I not book on the interrail website but rather on the website of each train company ?

There must be some error. You can try to book it but maybe there will appear an error.
In general it is cheaper if you book direct through the railway company. In this case you can use ÖBB website. Choose reduction “Interrail / EURail” and then it will show you the cheapest options.

Cheapest is seat for 14 euro. So the 32 euro on your screenshot are for 2 persons → 2x14 euro = 28 + 2x2 euro booking fee from Interrail = 32 euro. If you book through ÖBB you will save 4 euro.

In the case of NIghtjet trains, I would definitely suggest to book directly from the operator, ÖBB. https://tickets.oebb.at . As @MartinM says, book “normally” (do not attempt to click some “only seat” or somesuch), but make sure to choose Interrail/Eural as the reduction for each passenger. Then you will get the price for just the reservation in the seated/couchette/sleeping-car you want.

Thank you ! 

One more question On OBB site, there is no distinction between 1st class and 2nd class Interrail. Does that make a difference for night trains ? I assume not

For ÖBB nighttrains AFAIK makes no difference - 2nd class is sufficient. 
In other countries on nighttrains not operated by ÖBB it might make a difference.