There is no title that is too long but I rather it be less than 5. After 5 words, you know the fanbase is just going to abbreviate anyway, your not going to remember the exact title, and your never going to tell someone the exact title anyway.

The Lord of the Rings is 5 words. The absolute maximum before the title becomes a sentence. Don´t try to be more epic than the epic. I can maybe see 6 words working in edge cases but even that seems too much and individual novel names are their own thing where the 5 word limit equally applies.

I can´t think of a single one of these word salad LNs or manga titles that are worth looking at so the gimmick continues to remain the sign of a hack attention grabber.

Edit: October 2019. When Light Novel Titles Started to get so Long
https://www.youtube.com/watch?v=pi79l5k8gBM
I hate the LN market so much. The absolute ass crack of young adult literature and still comically niche outside of Japan.

IMO most of the best titles are under 6, but 'A Year and a Day in Old Theradane' comes to mind as a long title that I like (albeit not manga).

I dislike long titles when they're a sentence (or, horror of horrors, multiple sentences) and are describing the content of the work rather than making any attempt to be clever.

I don't particularly care about the length of the title, but this trend of writing the synopsis with the title not cool.

I do understand why it exists: It's the clickbait principle
The synopsis is a short, well written description to appeal to the interests of the readers, draw them in, and get them hooked on the main concept. However, it is not seen until you flip the book over or click the link.
The title, however is visible on the cover, website homepage, and every list/catalog - requiring no additional effort to be seen - but it doesn't have the captivating power of the synopsis.
So why not then write a very descriptive title to bait the readers even if it is long? It may be cumbersome, but it's surely effective.

Now, here's a suggestion: let's make this a thread for sharing the worst offenders...

I chose 9. The people who selected "There is no title that is too long" probably only do it to be contrary or something.🙄 Yeah, you people go and work through a 100-word-long title and then try and say again that there's no such thing as a title that's too long.🙄 Ultra long titles are ridiculous and can be contraproductive, unless done in an artful manner to get the attention of a specific target group of readers. For example, those super long novel titles that you repeatedly see here sound stupid, and aren't funny at all (not the translators' fault- they're just correctly translating it). Maybe it's different in the native languages, but I doubt that.

I picked 8, but realistically, it depends on the length of the words and how catchy the title. Immediately "One Flew Over the Cuckoo's Nest" came to mind and I really like that title (clocking in at 6 words and I threw in two more in case there are some titles with more prepositions).

I can't stand those super long isekai & light novel titles that are basically summaries of the manga. 😔