A : From my own experience with learning other languages and helping others learn Japanese, it usually takes at least two years of consistent daily study to start feeling comfortable speaking Japanese at an upper-intermediate level.
Of course, this depends on how often you study and the approach you take.
But let's not forget that everyone learns at their own pace. For some people, it might even take 4 or 5 years.
I've come across individuals who have been learning Japanese for more than 5 years and still struggle to hold a conversation.
The most important thing isn't the length of time, but how much effort you put into studying.
For example, if you study every day for 2 years, that's a total of 730 days.
365 days x 2 years = 730 days
If you study just 30 minutes a day, it adds up to 365 hours of study time.
30 minutes x 730 days = 365 hours
On the other hand, if you only study twice a week, you'd end up with just 104 days of study in 2 years, which is roughly 52 hours.
2 days a week x 2 years = 104 days
30 minutes x 104 days = 52 hours
So, the frequency and duration of your study sessions play a significant role in your progress.
The same 2 years of Japanese learning can result in either 365 hours of study time if you study every day for 30 minutes or just 52 hours if you study only twice a week.
In my case, I make it a habit to study intensely for at least 15 to 30 minutes every day, fully focused on the task at hand.
I also try to immerse myself in the language as much as possible by listening to music, watching videos, reading, and seizing any chance to have a conversation with native speakers.
With this approach, it usually takes around 2 years to start feeling comfortable speaking the language.
So from my experience, dedicating two years of hard work is a reasonable timeframe to reach an upper intermediate level.
By the way, according to certain online information, Japanese is considered one of the most challenging languages for English speakers to learn.
They claim that it takes about 2200 hours of study to reach proficiency.
If you study for 1 hour a day, it would take approximately 2200 days, which is roughly 6 years.
But honestly, I'm not quite sure what they mean by "proficiency".
Personally, I believe that if you commit at least 30 minutes to an hour every day for focused study and stay engaged with Japanese even outside of your study time, you should be able to hold a conversation within 2 years.
Building reading skills, especially with kanji (those Chinese characters), will take more time since there's quite a lot to learn.
But if your main focus is on speaking and understanding spoken Japanese, aiming for 2 years seems like a reasonable goal.