For visitors to Japanese hot springs and sento, the first hurdle is not the bath itself, but figuring out which entrance leads to the bath you should use. Signs are often in Japanese kanji only, and English labels are not always available. Accidentally entering the wrong bath is a mistake everyone wants to avoid.

The answer is simple: men’s baths are marked with “男,” and women’s baths with “女.” If you check these two characters on the entrance curtain or sign, you can identify the bath with near certainty. The curtain color is often blue or navy for men and red or pink for women, but colors vary by facility and are not absolute, so it is safest to confirm the kanji in the end.

Some hot spring inns also use a rotation system, where men’s and women’s baths switch by time of day. A bath that was men’s last time may be women’s the next time, so make it a habit to check the curtain characters every time you enter. This article organizes the practical kanji and signs that help you at hot springs, focusing on how to tell men’s and women’s baths apart. For why baths are usually separated by gender, see Why Are Japanese Hot Springs Usually Gender-Separated?. For how to use the changing room, see How to Use a Japanese Onsen Changing Room Step by Step. For bathing etiquette, see Basic Onsen Etiquette and How to Bathe.

First, check the two characters “男” and “女”

When you reach the entrance, look at the kanji on the curtain or wall sign. The basic rule is that men’s baths say “男” and women’s baths say “女.” If you remember just these two characters, you will not get lost in most facilities. Some places use different words instead, such as “殿方” for men’s baths and “婦人” or “ご婦人” for women’s baths, but either way there will always be a word showing which gender the bath is for.

The character “湯” is used for both baths. It is often combined with “男” or “女” as in “男湯” and “女湯,” so do not judge by “湯” alone. Look for the “男” or “女” before it. The readings are otoko-yu for men’s bath and onna-yu for women’s bath.

Some facilities write “otoko” and “onna” in hiragana instead of kanji, or include English labels such as “Men” and “Women.” If English labels are available, follow them. But if not, knowing how to distinguish “男” and “女” will help you in any facility.

Curtain color is a clue, but not a rule

Curtain color can also help. In Japanese hot springs and sento, men’s baths often use cool colors such as blue or navy, while women’s baths often use warm colors such as red or pink. It is tempting to rely on color alone, but there is a catch.

This color pattern is only a common tendency, not a rule. Facilities that prioritize design may use similar colors for both curtains, or change them seasonally. If you rely only on color, you may make a mistake at a place where the colors happen to be reversed. Treat color as a secondary clue, and always make your final decision by checking the kanji “男” or “女.” Even if the color makes you think it is probably one side, get into the habit of checking the letters before passing through the curtain.

In rotation systems, check every time you enter

One thing to watch for at Japanese hot spring inns is the rotation system, where men’s and women’s baths switch by time of day. This means the gender assignment of the two baths changes between night and morning, and many ryokan use it to let guests enjoy different views from the main bath or open-air bath.

In a rotation system, the place that was men’s bath the last time you used it may be women’s bath the next time. If you rely on memory and think, “This was men’s bath before,” you may enter the wrong one after it has switched. The fix is simple: check the curtain characters every time you bathe. The switching time is often posted at the changing-room entrance or front desk, so it is reassuring to confirm it at check-in. If you make a habit of rechecking every time, you will not get confused even in a rotation system.

Quick reference table of useful hot spring kanji and signs

Besides gender labels, there are many Japanese signs around baths. Here is a quick reference table of kanji that can be confusing if you do not know their meaning, along with their readings and definitions. The upper entries related to men and women are especially important to remember first.

Do not enter baths or doors marked “清掃中,” “準備中,” “入浴禁止,” or “立入禁止.” In particular, rotation-system inns may show “準備中” or “清掃中” before and after switching, so wait when those signs are displayed rather than trying to enter. In sauna facilities, “水” often means the cold plunge bath, where you cool down after the sauna.

Hot spring kanji you may see on bath notices

Bath areas and changing rooms often have signs explaining the type of water. Knowing the kanji related to source water and bath handling can help you understand what kind of bath it is. Here are the main ones.

• Gensen kakenagashi: a flow-through system that uses the natural spring water without recirculating it
• Kasui: water is added because the source is too hot or for other reasons
• Kaon: the water is heated because the source temperature is too low
• Junkan roka: a system that filters and recirculates the bath water
• Shōdoku: disinfected with chlorine or other agents for hygiene

These notices are required by law and show how the bath is managed. If you want to understand bath notices in more detail, see How to Read an Onsen Water Analysis Report. None of these kanji directly mean good or bad; they are simply objective information about how the water is treated.

Frequently asked questions

Can I tell men’s and women’s baths apart by curtain color?

Color can be a clue, but it is not reliable. Men’s baths often use blue or navy curtains, and women’s baths often use red or pink curtains, but this is only a tendency, not a rule, and some facilities use similar colors or even the opposite. Always make your final judgment from the kanji “男” or “女” on the curtain or sign.

If it only says “湯,” which bath is it?

“湯” is used for both men’s and women’s baths, so you cannot tell from that alone. Men’s baths are written as “男湯,” and women’s baths as “女湯,” with “男” or “女” in front. Do not decide based on “湯” by itself.

What is a rotation system?

It is a system where men’s and women’s baths switch by time of day. It is common at ryokan where the bath you can use or the view changes between night and morning. Because the gender assignment may be reversed from your last visit, check the curtain characters every time you bathe. Switching times are often posted at the front desk or in the changing room.

Are there signs written in kanji that I should be careful about?

Do not enter baths or doors marked “清掃中,” “準備中,” “入浴禁止,” or “立入禁止.” They indicate that the bath is being cleaned, being prepared, or not available for bathing. In rotation-system inns, these signs may appear before and after switching, so wait during those times.

What does “水” mean in a facility with a sauna?

In facilities with a sauna, “水” usually means the cold plunge bath. It is a cold tub used to cool down after the sauna, not drinking water. If you are unsure how to use it, it can help to watch how others use it or check the facility’s guide.

Summary

The answer to telling men’s and women’s baths apart in Japanese hot springs is simple: check the two characters “男” and “女” on the entrance curtain or sign. Curtain colors are often blue for men and red for women, but that is only a tendency, not a rule, so even if you think you have identified it by color, always confirm the kanji in the end. In rotation-system inns, where men’s and women’s baths switch by time of day, the assignment may be the opposite of last time, so checking the characters every time you enter is the safest habit.

If you also remember the meanings of signs such as “清掃中” and “準備中,” and that “水” in sauna facilities usually refers to the cold plunge bath, you can move calmly even in places without English labels. For the background behind gender-separated bathing, see Why Are Japanese Hot Springs Usually Gender-Separated?. For the changing-room process, see How to Use a Japanese Onsen Changing Room Step by Step. For bathing etiquette, see Basic Onsen Etiquette and How to Bathe.

Sources

• Ministry of Health, Labour and Welfare, “Hygiene Management Guidelines for Public Bathhouses” (basic rules for signage and hygiene management in public bathhouses)
• Japan Tourism Agency