Why doesn't 五つ or 五日 have a small つ?

I’m a new user and I’m in middle of learning the ~つ and ~日. All the other numbers that have two つ use a っ like and I was wondering why 五つ is an exception.

I think you’re a bit confused about what the small っ does - it’s not pronounced “tsu”, it “doubles” the following consonant. So みっつ isn’t “mitsutsu”, it’s “mittsu”

いつつ on the other hand is “itsutsu”, not “ittsu”


I don’t have a better answer than “because that’s the way it is”, although I can point out an other oddity in this pattern: 三つ編み (braided hair) is みつあみ and not みっつあみ like you would expect.

I don’t think they’re confused, they’re just understandably looking for a pattern to remember these baroque counter forms. Unfortunately I went through the same journey back when I was at that level and eventually had to face the grim reality: there’s no pattern, and you just have to memorize all these forms individually.


Yeah, “just memorize them” is the practical advice. Of historical interest, this blog post suggests that what happened is that originally the numbers which today have a small っ were originally monosyllabic; and that it’s only the monosyllabic ones that got gemination. Which both kinda accounts for why むっつ but いつつ (they were originally む and いつ plus counter つ, and む got lengthened) and why みつあみ (the original short form survived in some words). The old Japanese forms listed in the blog post match my other sources, at least; the rest is just speculation.


Just as an analogy, you can think of the role of the small tsu, っ (typed xtsu or xtu if you ever need to type it in IME), plays a similar role to the contraction-apostrophe in English, like: isn’t.

The apostrophe in this case represents how we sometimes change how we pronounce certain words. In English, the change is to ‘contract’ or remove part of the sound. Instead of n-o-t, you get n-t. In between the n and the t, you transition from one consonant to the other, with-holding the vowel sound. The effect is similar to ‘holding your breath’ (if only for a split second).

The small-tsu in Japanese also changes sounds, also by kind of ‘holding your breath’, but in this case for about the length of a ‘syllable’ (technically called a ‘mora’ for Japanese).

Now, be aware that I’m just making an analogy, to give you a sense of the role of っ in terms of how it affects pronunciation. It’s actually not really that similar to an apostrophe in other ways.

E.g. the word きっと (kitto in romaji), is pronounced “ki”, then hold breath (with tongue, ready to pronounce the upcoming t sound) for one mora, then “to”.

Or, you might imagine it, with an apostrophe to represent the ‘held breath pause’, as “ki ’ to”. But written in kana, the same thing is “きっと”.

1 Like

To cause pain. /s

Trust me when I say counters are a real early roadblock, especially when you think youve found a pattern only for it to fall apart. Take your lumps, and dont be afraid of failure and it’ll settle in eventually.

If you haven’t hit it already 四日, 四つ、ハ日、八つ still all cause me to pause due to thier phonetic similarities.

1 Like

Thank you! I didn’t realize- it all makes a lot more sense now.


this also lol. I love the language but GOD is it confusing sometimes. I was trying to latch onto a pattern but I guess I won’t even try to figure one out

I don’t think I know enough to understand the blog yet. That’s awesome though, I love learning about the history of languages, it’s always so cool

1 Like

I haven’t gotten to 四 in counters yet but I’m looking forward to it

There is some pattern when it comes to usage of っ. It tends to get used with making compound words where the first word ends in certain sounds (e.g. く and つ are common ones). You’ll start to see this kind of pattern lots when you learn the vocabs for kanji like 発 (はつ, departure).

1 Like

When I started I found that Tae Kim’s introduction to Japanese writing and phonetics helped: Chapter Overview – Learn Japanese (and following sections).

There’s a youtube video every time where he covers most of the important things.

1 Like