The West Valley Fault alone runs through 19 cities and municipalities in and around Metro Manila. Nationwide, millions of Filipinos live within a few kilometres of an active fault — and most have never checked. The good news is that it takes about two minutes, it's free, and the official tools are excellent. Here's exactly how.
Update: PHIVOLCS FaultFinder is temporarily unavailable
PHIVOLCS has taken FaultFinder offline while it addresses system security concerns, and it recommends HazardHunterPH in the meantime. We've updated this guide to match. Check the PHIVOLCS announcement for news on when FaultFinder will return.
1 Use HazardHunterPH (the official tool)
HazardHunterPH is the government's free hazard-assessment tool, run with PHIVOLCS. Enter an address and it reports the distance to the nearest active fault. It also covers ground shaking, liquefaction, landslide, flood and tsunami hazards for that spot. That's useful, because fault proximity is only one part of your real risk.
- Open HazardHunterPH on the web, or install the HazardHunterPH app on Android.
- Search for an address, or allow it to use your current location, or drop a pin on the map.
- Generate the hazard assessment for that location.
- In the seismic section, read the distance to the nearest active fault, along with the other earthquake hazards listed.
hazardhunter.georisk.gov.ph: generate a free hazard assessment report for any location.
2 When it's back: PHIVOLCS FaultFinder
FaultFinder is PHIVOLCS's dedicated tool for measuring the shortest distance between any location and the nearest active fault. Once it's available again, you can use it to double-check your HazardHunterPH result. Choose Valley Fault System (VFS) for Greater Metro Manila or Other Fault Systems for the rest of the country, set your location, and tap "Active Fault Nearest You."
3 Do a quick check on our live map
For a fast look, our own map has a fault layer built in:
- Open the Earthquakes PH live map.
- Under Map layers, switch on Active faults.
- Use the search box (or the 📍 button) to enter your city or area.
- The readout shows the nearest mapped fault and roughly how far away it is.
Treat this as a quick indicator. For anything official, such as permits, construction or insurance, use HazardHunterPH (or FaultFinder once it's back), which carry survey-grade data.
4 How close is "too close"?
There's no single magic number, but a few principles help you read the result:
- PHIVOLCS generally advises against building directly on or immediately astride a fault trace — a common guideline is a buffer of at least 5 metres on either side of the mapped line, to avoid the ground rupture itself.
- Beyond that setback, being "near" a fault (within a few kilometres) doesn't mean your home is doomed. Strong shaking affects a wide area regardless. What matters most is how your building is constructed and the type of ground it sits on.
- Fault maps have a margin of error, and not every fault is mapped. Use the distance as guidance, not a precise property line.
Found out you're near a fault? Don't panic.
It's information, not a verdict. Prioritise the things that actually save lives: anchor heavy furniture and appliances, have your building assessed by an engineer if it's old or was built before modern codes, know your evacuation route, and keep a go-bag ready. Millions live near faults safely by being prepared. See our earthquake safety guide for the full checklist.
Open the map, switch on Active faults, and search your address.
Related reading: Philippine fault lines and "The Big One", and why the Philippines has so many earthquakes.
Sources: HazardHunterPH; PHIVOLCS FaultFinder announcement. Always consult PHIVOLCS directly for official hazard assessments; third-party tools (including this site) are for guidance only.