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Seismic Wave ETA Calculator

Enter the origin time of a seismic event (in UTC), its distance from your location, and optionally its depth, and this tool estimates when the P wave and S wave should arrive. Arrival times are shown in UTC and in a time zone of your choice (default: US Pacific, which automatically shows PST or PDT as appropriate).

Travel times are interpolated from the ak135 reference Earth model (surface-focus first arrivals), so the estimates stay accurate even at teleseismic distances where waves dive through the faster deep mantle.

Event time (UTC):

Distance:

Depth (km):

Display time zone:

Estimates use an average Earth (ak135 model). Depth, if given, applies a correction — a 600 km deep focus brings the P wave in roughly a minute earlier than a surface focus. Beyond about 105° (~11,700 km) the direct S wave is blocked by the core and first arrivals are diffracted/core phases, so estimates there are rougher.

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