What’s the Difference Between “Puku Puku” and “Buku Buku” in Japanese?

Imagine a pot of soup starting to simmer — small, gentle bubbles rising to the surface.
Now imagine the same pot boiling over, with foam bubbling up quickly and aggressively.
In Japanese, these two states are described with two different sound words:

Puku Puku (ぷくぷく)

あわせて読みたい

What Is “Puku Puku”? The Sound of Bubbling or a Plump, Puffy Look Ever watched soup simmer with little bubbles popping at the surface? Or seen a baby’s round cheeks or a pufferfish puff up adorably? That’s when the Japanese…

Buku Buku (ぶくぶく)

あわせて読みたい

What Is “Buku Buku”? The Japanese Sound of Bubbling or Swelling Up (…in Size!) Ever watched bubbles rise quickly in boiling water?Or seen someone gain weight a little too fast, in a not-so-positive way? That’s when the Japanese onomatop…

They both describe the act of bubbling — but with a very different feel.

Differences Between Puku Puku and Buku Buku

Examples in Daily Life

Example 1: Gentle bubbles (Puku Puku)

The miso soup began to warm,
tiny bubbles forming softly —
puku puku…

Example 2: Overflowing foam (Buku Buku)

He added too much detergent,
and foam bubbled over —
buku buku…

Try Using Them!

• Watching gentle boiling? → Say puku puku
• Seeing foamy overflow or strong bubbling? → Say buku buku

They’re both bubbly — but one feels like a peaceful bath,
the other like you’ve overdone it.

Explore More: Comparison Series