How to Say Your Age and Birthday in Japanese

Talking about age and birthdays in Japanese is wonderfully practical. It comes up when making friends, filling out forms, talking about family, planning parties, and quietly panicking when someone asks your birth year and your brain suddenly becomes soup.

The good news: the main patterns are simple. The sneaky part is that Japanese uses counters, special readings, and date words that do not always behave like polite little textbook examples.

Classic Japanese. Mostly logical. Occasionally wearing a tiny chaos hat.

In this guide, you will learn how to say your age, ask someone’s age politely, say your birthday, talk about birth years, and use common birthday phrases. If you also want the celebration side of things, visit how to say happy birthday in Japanese. For introductions before the age talk begins, see what is your name and my name is in Japanese.

The Fast Pattern For Saying Your Age

The basic pattern is:

私は二十五歳です。
Watashi wa nijū-go-sai desu.
I am 25 years old.

In Japanese, age uses the counter 歳 sai, meaning “years old.” You can also see 才 sai, a simpler character often used informally or for children’s materials. For normal writing, 歳 is the standard choice.

How To Say “I Am ___ Years Old”

Use 私は watashi wa for “I,” add your age, then finish with です desu. In natural conversation, Japanese often drops the “I” if it is obvious. So both versions below are useful.

Age Numbers You Really Need To Know

Most ages are just number + 歳 sai. But a few ages have special readings. The biggest one is 二十歳 hatachi, meaning “20 years old.” Do not say nijussai for someone’s age unless you enjoy sounding like a badly printed worksheet.

Want to talk about relatives while giving ages? Pair this lesson with family in Japanese, because “my brother is 18” is more useful than “the mysterious floating human is 18.”

How To Ask Someone’s Age In Japanese

Age can be personal, so Japanese gives you several levels of directness. 何歳ですか nan-sai desu ka is simple and common, but with strangers or older people, use a softer phrase.

おいくつですか。
Oikutsu desu ka.
This is the safer polite choice when asking an adult’s age. Still, read the room. Japanese did not magically remove awkwardness from birthdays.

How To Say Your Birthday

The word for birthday is 誕生日 tanjōbi. To say “my birthday is…,” use this pattern:

私の誕生日は六月十五日です。
Watashi no tanjōbi wa roku-gatsu jū-go-nichi desu.
My birthday is June 15.

Japanese dates usually go from larger to smaller: year, month, day. So “June 15, 1998” becomes 一九九八年六月十五日 sen kyūhyaku kyūjū-hachi-nen roku-gatsu jū-go-nichi.

If your goal is to say the actual greeting, head to Happy Birthday in Japanese after this. First we are building the calendar muscles. Tiny muscles, but important.

Months In Japanese For Birthdays

Months are easy because Japanese uses numbers plus 月 gatsu. January is “one month,” February is “two month,” and so on. For birthdays, this is very merciful.

Days Of The Month You Need For Birthdays

The days of the month are less obedient. The 1st through 10th have special readings, and the 14th, 20th, and 24th also need attention. This is where Japanese looks at your calendar and says, “Cute. I made it art.”

For the other days, you usually use number + 日 nichi, like 十五日 jū-go-nichi for the 15th or 三十一日 sanjūichi-nichi for the 31st.

How To Say Your Birth Year

The word 年 nen means “year.” To say the year you were born, use 生まれ umare, meaning “born.” The pattern is:

一九九八年生まれです。
Sen kyūhyaku kyūjū-hachi-nen umare desu.
I was born in 1998.

You can also say the full sentence with 私は watashi wa, but in conversation, the shorter version is natural when the topic is already you.

Useful Birthday And Age Sentences

Here are real-life sentences you can use in conversation, messages, forms, or that one awkward moment when someone asks your age and you briefly forget what numbers are.

Polite, Casual, And Natural Versions

Japanese changes depending on who you are talking to. With friends, shorter phrases are fine. With teachers, coworkers, customers, or new adults, polite phrases are safer. Yes, even if everyone is smiling. Especially if everyone is smiling.

Talking About Age With Time Words

Age and birthdays often appear with time words like today, tomorrow, next month, and this year. If you want a deeper calendar and clock lesson, visit time in Japanese.

And if you are talking about the year changing, holidays, or January birthdays, Happy New Year in Japanese is a handy next stop.

Common Mistakes And Quick Fixes

These are the little traps that catch learners again and again. Nothing dramatic. Just enough to make your sentence sound like it tripped over a shoe.

Mini Practice: Build Your Own Sentences

Try swapping the age, month, day, or year. Read the Japanese first, then check the rōmaji and English. Your mouth may complain at 二十歳 hatachi. Let it complain. It will survive.

Quick Reference Summary

Yak Takeaway

To talk about age in Japanese, remember 歳 sai for “years old,” 二十歳 hatachi for “20 years old,” and 誕生日 tanjōbi for “birthday.” To say your birth year, use 年生まれ nen umare, as in 一九九八年生まれです sen kyūhyaku kyūjū-hachi-nen umare desu.

Start with one sentence today: 私は___歳です。 Watashi wa ___-sai desu. Then add your birthday: 私の誕生日は___です。 Watashi no tanjōbi wa ___ desu. There. You can now reveal your age, dodge your age, or announce your birthday with dignity. Mostly.

For more Japanese basics, continue through the Learn Japanese hub.