19/09/2025
Currently reading: L’usage du Japon, Emmanuel Ruben
I finally took some time to do some basic maths to estimate how long it would take to learn all the JLPT vocabulary. I used the word counts for each level from Kanpai-Japan.com.
Level |
Kanpai |
Bunpro |
N5 |
800 |
1100 |
N4 |
1600 |
2200 |
N3 |
3000 |
4200 |
N2 |
6000 |
6198 |
N1 |
10000 |
9172 |
If I take today’s date, compute how many days are left until each JLPT sessions (taking 1st of June / December), this gives the following table:
|
|
N5 |
|
N4 |
|
N3 |
|
N2 |
|
N1 |
|
|
Day left |
Kanpai |
Bunpro |
Kanpai |
Bunpro |
Kanpai |
Bunpro |
Kanpai |
Bunpro |
Kanpai |
Bunpro |
1/12/25 |
73 |
11.0 |
15.1 |
21.9 |
30.1 |
41.1 |
57.5 |
82.2 |
84.9 |
137.0 |
125.6 |
1/6/26 |
255 |
3.1 |
4.3 |
6.3 |
8.6 |
11.8 |
16.5 |
23.5 |
24.3 |
39.2 |
36.0 |
1/12/26 |
438 |
1.8 |
2.5 |
3.7 |
5.0 |
6.8 |
9.6 |
13.7 |
14.2 |
22.8 |
20.9 |
1/6/27 |
620 |
1.3 |
1.8 |
2.6 |
3.5 |
4.8 |
6.8 |
9.7 |
10.0 |
16.1 |
14.8 |
1/12/27 |
803 |
1.0 |
1.4 |
2.0 |
2.7 |
3.7 |
5.2 |
7.5 |
7.7 |
12.5 |
11.4 |
1/6/28 |
986 |
0.8 |
1.1 |
1.6 |
2.2 |
3.0 |
4.3 |
6.1 |
6.3 |
10.1 |
9.3 |
1/12/28 |
1169 |
0.7 |
0.9 |
1.4 |
1.9 |
2.6 |
3.6 |
5.1 |
5.3 |
8.6 |
7.8 |
1/6/29 |
1351 |
0.6 |
0.8 |
1.2 |
1.6 |
2.2 |
3.1 |
4.4 |
4.6 |
7.4 |
6.8 |
1/12/29 |
1534 |
0.5 |
0.7 |
1.0 |
1.4 |
2.0 |
2.7 |
3.9 |
4.0 |
6.5 |
6.0 |
1/6/30 |
1716 |
0.5 |
0.6 |
0.9 |
1.3 |
1.7 |
2.4 |
3.5 |
3.6 |
5.8 |
5.3 |
1/12/30 |
1899 |
0.4 |
0.6 |
0.8 |
1.2 |
1.6 |
2.2 |
3.2 |
3.3 |
5.3 |
4.8 |
This is assuming a 100% accuracy, and being able to retain everything immediatly, and this should come along kanji / grammar / listening study. However, I still feel it gives a good overview of the thing.
With the 80% accuracy rate
If I assume that I’m retaining only 80% of the new words (meaning every 10 cards reviewed, I forget 2 of them), I should multiply everything by 1.25 (x * 0.8 = 10 <=> x = 12.5)
|
|
N5 |
|
N4 |
|
N3 |
|
N2 |
|
N1 |
|
|
Day left |
Kanpai |
Bunpro |
Kanpai |
Bunpro |
Kanpai |
Bunpro |
Kanpai |
Bunpro |
Kanpai |
Bunpro |
1/12/25 |
73 |
13.7 |
18.8 |
27.4 |
37.7 |
51.4 |
71.9 |
102.7 |
106.1 |
171.2 |
157.1 |
1/6/26 |
255 |
3.9 |
5.4 |
7.8 |
10.8 |
14.7 |
20.6 |
29.4 |
30.4 |
49.0 |
45.0 |
1/12/26 |
438 |
2.3 |
3.1 |
4.6 |
6.3 |
8.6 |
12.0 |
17.1 |
17.7 |
28.5 |
26.2 |
1/6/27 |
620 |
1.6 |
2.2 |
3.2 |
4.4 |
6.0 |
8.5 |
12.1 |
12.5 |
20.2 |
18.5 |
1/12/27 |
803 |
1.2 |
1.7 |
2.5 |
3.4 |
4.7 |
6.5 |
9.3 |
9.6 |
15.6 |
14.3 |
1/6/28 |
986 |
1.0 |
1.4 |
2.0 |
2.8 |
3.8 |
5.3 |
7.6 |
7.9 |
12.7 |
11.6 |
1/12/28 |
1169 |
0.9 |
1.2 |
1.7 |
2.4 |
3.2 |
4.5 |
6.4 |
6.6 |
10.7 |
9.8 |
1/6/29 |
1351 |
0.7 |
1.0 |
1.5 |
2.0 |
2.8 |
3.9 |
5.6 |
5.7 |
9.3 |
8.5 |
1/12/29 |
1534 |
0.7 |
0.9 |
1.3 |
1.8 |
2.4 |
3.4 |
4.9 |
5.1 |
8.1 |
7.5 |
1/6/30 |
1716 |
0.6 |
0.8 |
1.2 |
1.6 |
2.2 |
3.1 |
4.4 |
4.5 |
7.3 |
6.7 |
1/12/30 |
1899 |
0.5 |
0.7 |
1.1 |
1.4 |
2.0 |
2.8 |
3.9 |
4.1 |
6.6 |
6.0 |
I believe the first table is more accurate, as revision should become more intensive getting closer to the JLPT. Also, the 80% accuracy rate is quite flexible and should probably increase as we become more familiar with the language.
I should probably do the same for kanji, but WaniKani is here for that, no need to think, just do the daily lessons / reviews and basta.
Also today, thanks to this forum post, I discovered this website offering comprehensible input, graded by level. It’s a great way to get used to Japanese itself, and pick up some cool new words like 肩.