Hey, so I’m having difficulty differentiating when to use each. I’m using Tobira, but still, for me, both seem to fit.
“The cost depends on the hotel room.”
“The cost changes depending on the hotel room”
I don’t really see the difference. Could anyone please help me with this? 感謝します。
But that’s the thing if
“The cost is due to the room you stay in”
“The cost changes based on the room you stay in”
Isn’t that meaning the same thing? That cost depends on room?
I may be wrong, but I think there’s really no difference in meaning in this context.
The confusion is coming from the fact that によって、による、により all mean the same things (Depends on, Depending on, due to, by means of). The English is going to change based on context, of course. When you add 違う, you’re simply adding “It’s different” to “Depending on”, that’s pretty much it. Your first two examples perfectly illustrate this:
“The cost depends on the hotel room.”
“The cost changes (it’s different = 違う) depending on the hotel room”
So the meaning is the same in the end? It’s almost a synonym in this case, right? I was messing up a few exercises on it here and on the tobira book.
They are basically synonyms. The difference is in the details, as is true for English. For starters, they both have による as a base. So we can immediately assume that the ‘depending on’ meaning applies. From here, the only work we need to do is look at the difference (違う), and then decide for ourselves if it is significant, or superfluous.
In English, just like almost every other language, we add extra words to sentences based on many things. Politeness, the need/lack of need for context, the person we’re talking to, the point we want to emphasize, etc etc. In this case, let’s pretend that a receptionist says both of these.
Clerk - ‘The price differs depending on the room.’ (Sounds polite as more words/description is added)
Clerk - ‘The price depends on the room.’ (Potentially sounds a bit less polite, due to the elimination of any excess language.
Now the same conversation with a friend after asking them about room prices.
Friend - ‘Price will differ depending on the room.’ (Quite polite for a friend, might make you feel like they’re being standoffish)
Friend - ‘Depends on the room.’ (Sounds friendly and pretty much exactly what you would expect them to say.
To answer your question conclusively. Yes, they are the same. But context will play a large part in how natural something sounds in almost all cases. Both English and Japanese are languages where sentences tend to get longer as politeness increases. Use this as a (rough) rule when deciding what sounds better in any case.
Additionally, the final verb in a sentence generally carries the most importance and strongest emphasis. When the final verb is “による,” the focus is placed more on the dependent nature. On the other hand, when “違う” is the final verb, the emphasis is shifted to the object being different.
It’s worth noting that “による” has other extended meanings that are not quite compatible with “違う.” These extended meanings involve causation or something being according to a certain source.
Examples:
I included the “by means of” meaning in my previous explanation, but not the “according to” (によると) since that’s technically a different grammar point. I thought about it, but decided not to.
The thing is that Japanese is a VERY economical language in that it’s constantly recycling itself. Think about all the ways particles like で (to separate な adjectives, to indicate a method of doing something, a quantity for a certain price, location of an action, etc), and に (to indicate time, point towards a person or a place, indicate a change, etc) are used to mean different things; or grammar points that use ところ (https://jlptsensei.com/page/1/?s=ところ) or ばかり (https://jlptsensei.com/page/1/?s=ばかり), for example, to mean completely different things!
I guess I didn’t want to create more confusion but, at the same time, I probably should’ve included it. Good call!
Lovely. It makes more sense now 
For the によって違う exercises on here it always accepts による though right? At least that’s been the case for every sentence I’ve done until now.
I’ve actually started marking myself wrong if the lesson is によって違う and I use による because I realized I was getting by with the latter and completely forgot the former.