If you just felt shaking, the fastest way to confirm an earthquake is the USGS “Latest Earthquakes” map at earthquake.usgs.gov, which posts a preliminary magnitude and location within one to three minutes of any quake above roughly magnitude 2.5 in the United States. During the shaking, drop to the floor, cover your head and neck under a sturdy table, and hold on until it stops; after it stops, check for gas smells and injuries before you check your phone. Most people who are hurt in U.S. earthquakes are hit by falling objects while trying to run, not trapped by collapsing buildings.
Key Takeaways
- Confirm it: earthquake.usgs.gov (map) or the USGS “Did You Feel It?” page; California, Oregon and Washington residents also get ShakeAlert warnings on their phones seconds before strong shaking
- During: Drop, Cover, Hold On โ do not run outside, do not stand in a doorway
- After: expect aftershocks; check for gas leaks, water, and structural cracks before re-entering rooms
- Report your experience on “Did You Feel It?” โ it improves the USGS shaking map for everyone
- Prepare: two-week water supply, a wrench for the gas valve, secured bookcases and water heater
How to check if it was an earthquake (and how big)
| Source | What it shows | How fast |
|---|---|---|
| USGS Latest Earthquakes map (earthquake.usgs.gov/earthquakes/map) | Magnitude, depth, location, time; filter by past hour/day and magnitude | 1โ3 minutes for M2.5+, sometimes under a minute in California |
| USGS “Did You Feel It?” (DYFI) | Crowd-sourced intensity map; you can submit your own report | Live as reports come in |
| ShakeAlert / MyShake app (CA, OR, WA) | Early warning before shaking arrives, plus confirmation after | Seconds before shaking for M4.5+ |
| Android Earthquake Alerts | Built-in alerts on Android phones nationwide, using phone accelerometers | Seconds before to seconds after |
| Local news / X search “earthquake now” | Fast confirmation that others felt it | Immediate but unverified |
Two things trip people up. First, the very first magnitude posted is preliminary and is often revised up or down by a few tenths within the hour; a quake reported as M4.4 may settle at M4.2. Second, the map defaults to showing M2.5 and above worldwide, so if you felt something small in a region with dense sensors, switch the filter to “all earthquakes” for the past day. Small events (M2.0โ3.0) are common in California, Oklahoma, Alaska and Hawaii and are rarely worth worrying about.
What to do during the shaking
- Drop to your hands and knees before the shaking knocks you down.
- Cover your head and neck with your arms. If a sturdy table or desk is within a step or two, crawl under it. If not, crawl next to an interior wall away from windows and tall furniture.
- Hold on to your shelter until the shaking stops; furniture can slide.
- If you are in bed, stay there and cover your head with a pillow.
- If you are driving, pull over away from overpasses, power lines and buildings, set the parking brake, and stay in the car.
- If you are outside, move away from buildings, streetlights and utility wires and get low.
The doorway advice is outdated: modern doorframes are no stronger than the rest of the wall and put you in the path of a swinging door and people trying to leave. Running outside during shaking is the single most common cause of injury in U.S. quakes because of falling facade pieces, glass and signs.
The first hour after
- Expect aftershocks. After a moderate quake, several smaller ones in the following hours are normal, and a larger one is possible but uncommon (roughly 1 in 20 quakes is followed by a bigger one within a week).
- Check for gas. If you smell gas or hear hissing, open windows, leave the building, and shut off the gas at the meter with a wrench. Do not turn it back on yourself; the utility must do it.
- Check for water and electrical damage. Shut off water at the main if pipes are broken; shut off electricity at the breaker if you see sparks or damaged wiring.
- Look at the structure. Cracks in drywall are cosmetic; diagonal cracks in masonry, doors that no longer close, or a house that has shifted on its foundation mean you should stay out until it is inspected.
- Use text, not calls. Networks jam after a widely felt quake; texts get through when calls do not. Register on the Red Cross “Safe and Well” site if family is worried.
- Submit a “Did You Feel It?” report. It takes 90 seconds and directly improves the intensity map that emergency managers use.
What the magnitude numbers actually mean
| Magnitude | Typical experience | Damage |
|---|---|---|
| 2.5โ3.9 | Felt indoors by some; like a truck passing | None |
| 4.0โ4.9 | Felt by most; dishes rattle, hanging objects swing | Minor, mostly to contents |
| 5.0โ5.9 | Strong shaking; hard to stand near the epicenter | Damage to poorly built structures, chimneys |
| 6.0โ6.9 | Violent near the epicenter | Serious damage within tens of miles |
| 7.0+ | Major | Widespread damage; regional emergency |
Magnitude is logarithmic: each whole number is about 32 times more energy. Distance and depth matter as much as magnitude โ a shallow M4.5 directly under a suburb is felt far more sharply than a deep M5.5 offshore. The USGS ShakeMap, linked from each event page, shows estimated shaking intensity by location and is the better guide to what happened where you are.
Preparing before the next one
- Water: one gallon per person per day for at least two weeks in earthquake country; water mains are the first utility to fail.
- Secure the house: strap the water heater, anchor bookcases and TVs, install latches on upper cabinets, and move heavy items to low shelves.
- Gas wrench and flashlight by the bed, with sturdy shoes โ broken glass is the most common post-quake injury at home.
- Know your shut-offs: gas meter, water main, electrical panel. Label them.
- Insurance: standard homeowners and renters policies exclude earthquake damage. In California, insurers must offer a separate policy (often through the California Earthquake Authority); elsewhere it is an optional endorsement. Deductibles are typically 10โ20% of the dwelling limit.
- Enable alerts: MyShake app in CA/OR/WA, and confirm Android Earthquake Alerts or iOS emergency alerts are switched on.
FAQ
Why did my phone alert me before I felt anything?
ShakeAlert detects the fast-moving P-wave near the epicenter and pushes a warning that outruns the slower, damaging S-wave. Depending on your distance you get anywhere from zero to tens of seconds. Use them to drop and cover.
Why does the magnitude keep changing on the USGS page?
The first solution uses the nearest sensors; as data from more distant stations arrives, seismologists refine the location, depth and magnitude. Revisions of 0.1โ0.3 are routine.
Can earthquakes be predicted?
No. Scientists can estimate long-term probabilities for a fault and issue aftershock forecasts, but there is no reliable way to predict a specific quake’s time, place and size.
Should I leave the building after the shaking stops?
Only if you see structural damage, smell gas, or are told to by authorities. Otherwise stay put, check on others, and wait for aftershocks to settle before moving around outside where debris may still fall.
Sources
- U.S. Geological Survey โ Latest Earthquakes, Did You Feel It?, ShakeAlert
- Ready.gov โ Earthquakes
- California Earthquake Authority โ insurance basics
- Great ShakeOut โ Drop, Cover, Hold On guidance
This guide covers general preparedness; follow local emergency management instructions during an actual event. Last updated September 3, 2026 ยท InfoBrief Staff









