How to get the free child tickets on int.bahn.de?

Are you inputting your children's dates of birth? It should take that into account and give you the discount.

I would suggest you read this FAQs page about traveling with children on the Deutsche Bahn website, as this will give you the information you need.

https://int.bahn.de/en/offers/additional-services/travelling-with-children

Thanks Mardee! Yes I did read that FAQ and I've Googled, which is why I'm confused as to why it's not lowering the fare. I did input their ages, it didn't ask for their DOB, just ages. I tried fare for 1 adult and it is €73, then I add another adult and it goes to €146, then I add the 3 kids (with ages input) and it jumps to €255, so it is charging 50% fare for the kids when it should be free, no?

I just realized that you were traveling from Paris to Germany. I think there is an issue with that, and the free discount does not apply for the portion of the ticket that travels through France, although I think that they get a 50% discount. So that might be what's happening here. Let me check on that, and I'll come back.

EDIT: Yes, that's the problem. Because you are traveling through France, the children only get a 50% discount. It is not free for that portion. So that's the issue there. If you wanted to be completely free, you would need to be traveling through Austria, Belgium, Bulgaria, Croatia, Czechia, Denmark, Finland, Hungary, Luxembourg, Montenegro, Serbia, Slovakia, Slovenia, and Sweden. https://int.bahn.de/en/faq/children-flexible-fare-europe

Ah ok, the way I read it on the website it seemed like they would be free for the the entire trip, thanks for finding that link! I missed that one. I wonder if it would be better to buy separate tickets then and get us from Paris to a station just over the border, and then continue on in Germany with the free child fare? Or is the complication not worth the savings, hm.

That certainly might work. You might want to do a dummy booking for both and see what prices you come up with. That's what I would do. As far as whether it's worth it, I guess that would depend on how much money you saved and how much time it would take.

Yes I'm going to do that comparison now. Well at least I know I wasn't missing anything, thanks for helping me with that :)

You're welcome! I'm sure you will have a wonderful trip!

A trip from Paris to Rust, Germany, will undoubtedly go through Strasbourg, then across the Rhein through Kehl, Germany, to Offenburg, then on the main line up the Rhein to Rust. I have (or had, they were elderly when I last saw them over 20 years ago) relatives in a village outside of Lahr, about 7 miles north of Rust. I visited them twice on consecutive weekends in the 1980s, once coming from Paris and once coming from Brussels. Both times I arrived in Strasbourg late at night and stayed in a hotel near the main station in Strasbourg, then came across the river first thing in the morning. I had breakfast in Offenburg, then went on to Lahr. Almost all of the trip from Paris to Rust will be in France by express trains, probably TGVs, where you only get the 50% discount.

It's a very short trip from Strasbourg to Kehl, which is just ¼ mile from the border into Germany. From there, it's a short trip by regional train and bus to Rust.

Thank you Lee :)