Historical tsunamis · Sep 11, 1921, 4:01 AM UTC
1921 Java tsunami
Indonesia
The tsunami of Sep 11, 1921, 4:01 AM UTC originated near Java (Indonesia).
Key facts
- Date
- Sep 11, 1921, 4:01 AM UTC
- Cause
- Earthquake
- Magnitude
- M7.5
- Maximum documented water height
- 0.10 m
- Observation records
- 3
- Countries affected
- 2
It was triggered by a magnitude 7.5 earthquake.
The highest documented water height was 0.10 m (Tjilatjap, Sumatra, Indonesia).
3 observation sites in 2 countries are recorded.
Map of observation sites
3Each dot is a documented observation site; colour and size show the observed water height. The triangle marks the source.
Observations by country
| Country | Observation records | Maximum documented water height | Deaths | Earliest arrival |
|---|---|---|---|---|
| Indonesia | 2 | 0.10 m Tjilatjap, Sumatra | — | — |
 Vietnam | 1 | — | — | — |
Highest documented water heights
3 / 3Individual documented observations for this event. Heights come from different measurement types and sources; not every location has a measured height.
| Location / station | Observed height | Distance from source | Country |
|---|---|---|---|
| Tjilatjap, Sumatra · Central Java | 0.10 m | 422 km | Indonesia |
| Parang Tritis · Yogyakarta | — | 338 km | Indonesia |
| Spratly Islands | — | 2,180 km | Vietnam |
More tsunamis
Source: NOAA National Centers for Environmental Information (NCEI), Global Historical Tsunami Database. Confirmed events only. Deaths and damage are database estimates; older records are incomplete. Water heights come from different types of observation.