The Japanese counting system is rather complex, and students of the language may struggle to know and remember how to use it. This article will attempt to present how to say cardinal numbers as clearly and concisely as possible. Here we go…

One: ichi 一
Two: ni 二
Three: san 三
Four: yon / shi 四
Five: go 五
Six: roku 六
Seven: nana / shichi 七
Eight: hachi 八
Nine: kyuu 九
Ten: juu 十
Twenty: ni juu 二十
Thirty: san juu 三十
Forty: yon juu 四十 (Note: shi juu is wrong!)
Fifty: go juu 五十
Sixty: roku juu 六十
Seventy: nana juu 七十 (Note: shichi juu is wrong!)
Eighty: hachi juu 八十
Ninety: kyuu juu 九十
One hundred: hyaku 百
One thousand: sen 千

For numbers from 11 to 99, just break them down, and append the two figures you get. For example, “eleven” is 10 and 1, so it’s “juu ichi” 十一. “Twenty five” is 20 and 5, so it’s “ni juu go”　二十五 and so on. “Shi” and “shichi”, the alternative pronunciation for “four” and “seven” respectively, are uncommon and cannot be appended to other numbers. Therefore, you should not say “go juu shi” for “fifty four”, but “go juu yon” instead. Likewise, if you want to say “thirty seven”, “san juu shichi” is wrong. Say “san juu nana” instead.
Once you’ve gotten used to numbers from 1 to 100, it’s not that hard to figure out how to say numbers between 100 and 1000. Note that “one hundred” is “hyaku”, and not “ichi hyaku”. For “two hundred”, add “ni” in front. So you get “ni hyaku”. “Five hundred” is “go hyaku”, and so on. “One hundred and sixty eight” is “hyaku roku juu hachi” 百六十八, “seven hundred and forty five” is “nana hyaku yon juu go” (note that “shi” cannot be used in place of “yon” here, as explained above) 七百四十五 and so on.

Be careful with “three hundred” and “six hundred”: “Three hundred” is pronounced as “san byaku” instead of “san hyaku”. “Six hundred” is “roppkyaku” and not “roku hyaku”. The reason is that due to the position of the mouth, it’s easier for the Japanese people to pronounce them.

Next up is “thousand”. If you have no problems saying numbers up to 999, numbers from 1000 to 9999 shouldn’t pose any problem as well. Similar to “one hundred”, “one thousand” is not “ichi sen”, but simply “sen”. For “two thousand”, append the “ni” to get “ni sen”. The only thing you have to look out for is “three thousand”. Instead of “san sen”, it’s pronounced as “san zen”. This rule is also catered to the Japanese people’s convenience.
From 10,000, things get somewhat tricky. The Japanese do not say “juu sen” for “ten thousand”, but say “ichi man” 一万 instead. “One hundred thousand” is “juu man” 十万, and “one million” is “hyaku man” 百万. “Ten million” is “issen man” 一千万. Note that it’s not “sen man” or “ichi sen man”. Yes, how wonderful, isn’t it?

Once you are familiar with cardinal numbers, you will be ready to learn how to count objects, as well as say dates and time in Japanese and the like. Have fun~