But have you ever wondered, how many i-adjectives are there?
And how many な na-adjectives?
How many な na-adjectives end with い (i) sound?
Let’s look into that.

We analyzed our data source and here are the stats:

Count Percentage
na-adjectives 6027 69.38%
i-adjectives 2660 30.62%


As you can see, na-adjectives are more common - being 69.38% of all Adjectives. i-adjectives take up the rest - 30.62%

Do i-adjectives always end on い (i)?

Count Percentage
i-adjectives ending with い (i) 2660 100%
i-adjectives with different ending 0 0%


Short and sweet - YES - 100% of i-adjectives end with い (i). No exceptions.



Na-adjectives are a bit more tricky - some of them end on い (i) sound and therefore may sound like i-adjectives.

How many, you ask?

Count Percentage
na-adjectives NOT ending with い (i) 5404 89.66%
na-adjectives ending with い (i) 623 10.34%


na-adjectives ending with い (i) take up about 10% of all na-adjectives.

To combine, adjectives from both groups that end on い (i):

Count Percentage
i-adjectives 2660 78.39%
na-adjectives ending with い (i) 623 21.61%


You can see that 78.39% of all Adjectives ending in い (i) are i-adjectives.
Only little more than 21% are na-adjectives.


If you encounter an adjective ending on い (i) and you have no idea in which group the adjective belongs to, you can try betting on い (i) adjective group.


You may still be wrong, of course, but you have higher chance of being right.

Disclaimer:

These statistics do not precisely reflect the whole language! Consider all numbers to be approximate!
As mentioned before, we analyzed our data source - JMdict-EDICT Dictionary Project to create these statistics.
The data source does not cover all existing words and may contain errors.
Language is like a living organism, it evolves and changes over time.