は vs. が: the difference, finally explained

The core idea: topic vs. subject

English only has a subject. Japanese has two layers:

• The topic, marked with は, sets the stage: as for this, here’s what I want to say.
• The subject, marked with が, is who or what does the action or has the quality.

Often they’re the same thing, and は wins. But the distinction becomes visible when they differ. Here’s a famous example:

• ▶︎
  ぞうははながながいzō wa hana ga nagai
  Elephants have long trunks.Literally: as for elephants (topic), the trunk (subject) is long.

The topic is elephants, but what’s long is the trunk. Two particles, two jobs. Keep that picture in mind, and the rules below will make sense.

Rule 1: は introduces the topic

When you start talking about something, mark it with は. Self-introductions are the classic case:

• ▶︎
  わたしはがくせいですwatashi wa gakusei desu
  I am a student.As for me: student.
• ▶︎
  きょうはあついですkyō wa atsui desu
  It’s hot today.As for today: hot.

Once a topic is set, Japanese usually doesn’t repeat it. That’s why so many Japanese sentences have no visible subject at all.

Rule 2: が marks new information

Think of it like a spotlight. は points at what we’re talking about; が puts the spotlight on the word right before it. That’s why が is used when something new appears or when the subject itself is the important information.

• ▶︎
  あ、ねこがいる！a, neko ga iru!
  Oh, there’s a cat!The cat is new information. You just noticed it.
• ▶︎
  ねこはどこ？neko wa doko?
  Where’s the cat?Now the cat is the known topic.

Rule 3: Question words take が

Words like だれ (who) and なに (what) are, by definition, unknown information. So they are marked with が, and so is the answer:

• ▶︎
  だれがきましたかdare ga kimashita ka
  Who came?
• ▶︎
  たなかさんがきましたTanaka-san ga kimashita
  Tanaka-san came.The answer fills the gap, so it keeps が.

Rule 4: は for contrast

は can also contrast one thing with another, often with an implied but:

• ▶︎
  にくはたべませんniku wa tabemasen
  I don’t eat meat.Implies: (but I eat other things).
• ▶︎
  コーヒーはすきですが、こうちゃはすきじゃないですkōhī wa suki desu ga, kōcha wa suki ja nai desu
  I like coffee, but not black tea.

This is why は appears so often in negative sentences: saying you don’t do something naturally contrasts it with things you do.

Rule 5: Some words always use が

A handful of very common words mark their “object” with が instead of を. Just learn them as fixed patterns:

Put rules 1 and 5 together and you get a very common pattern: わたしはねこがすきです, As for me, cats are liked, or simply: I like cats.

Bonus: が inside descriptions

When a mini-sentence describes a noun, its subject uses が, even if it would otherwise be a topic:

• ▶︎
  わたしがつくったケーキwatashi ga tsukutta kēki
  the cake (that) I made

You won’t need this in your first weeks, but it explains many “strange” が you’ll see later.

Cheat sheet

Don’t worry too much

Even advanced learners sometimes mix them up, and native speakers will still understand you. Start with the five rules, notice the particles in every sentence you read, and your intuition will grow faster than you think.

New to Japanese? Start with our beginner’s guide and the hiragana chart.

Frequently asked questions