Where each finding comes from and how it is read

CAL FIRE sorts land into three hazard classes. Each zone is a polygon covering an area, not a rating attached to a parcel or a building.

Hazard is not risk

This is the distinction that matters most, and the one the word "zone" tends to obscure. Hazard describes the long-run physical conditions of a landscape: what grows there, how steep it is, how it burns and how far embers travel when it does. It is a statement about the ground over decades, not a forecast for this season.

Risk is a different question. It asks what would actually happen to a particular building, and so it depends on the roof, the vents, the windows, the clearance around the walls and what the neighbors have done with theirs. None of that is in this data. Two houses on the same street sit in the same zone whether or not one of them has been hardened.

Two packages, two responsibility areas

Responsibility for wildfire protection in California is split, and so is the mapping. The state is responsible for the State Responsibility Area, and cities and counties for the Local Responsibility Area. CAL FIRE publishes the two as separate packages, and this site loads both:

• The State Responsibility Area zones, from the FHSZSRA_23_3 package
• The Local Responsibility Area zones, from the data package dated 24 March 2025

The two differ in more than geography. Only the local data carries the Non-wildland classification; every polygon in the state data is Moderate, High or Very High. The report names which responsibility area a point falls in, because it determines who writes the rules that follow from the zone.

Where zones overlap

The zone lookup asks which zone polygons contain the point. Almost always exactly one does, and its class is the answer.

Where polygons overlap, as they can along the seam between the state and local datasets, the report gives the most hazardous class it finds rather than picking one dataset over the other. It is the conservative reading, and it means a point on a boundary will never be shown as safer than one of its sources says it is.

What the map cannot tell you

Zone edges follow modeled terrain and vegetation, not property lines. A boundary drawn through a neighborhood is not survey-accurate, and a parcel near one may be classified differently by the authority that regulates it than by a point lookup on the map.

The published zones also change, and local government has a say in them. A city or county adopts the State Fire Marshal's recommendation by ordinance, and under Government Code section 51179 it may add areas or raise a class, but it may not lower one. So the zone your jurisdiction enforces can be more severe than the state map this site draws, never less. The map shows the packages named above and nothing more recent.

The High Fire-Threat District is the California Public Utilities Commission's map of where utility power lines carry a greater risk of starting a wildfire that spreads quickly and does great damage. The Commission set its rules in decision D.17-12-024 and adopted the map in January 2018, and utilities working in it must inspect their lines more often, clear vegetation farther from them and fix problems sooner. It rates a risk of ignition from the grid, not the hazard of the land itself, so it is drawn separately from the zones above and does not follow their edges.

What is loaded

Tiers 2 and 3 are loaded from the Commission's own map service, which it updates in place and which is newer than the downloadable files linked from its website. Tier 1 is left out: it is the tree mortality High Hazard Zones designated by the Forest Service and CAL FIRE, last revised in 2020, rather than a tier of the Commission's fire-threat map. Where the two tiers overlap in slivers along their shared border, the report gives the higher one.

CAL FIRE's Fire and Resource Assessment Program keeps the state's record of wildfire perimeters, compiled with the Forest Service, the Bureau of Land Management, the National Park Service and the Fish and Wildlife Service and released each spring. It reaches back to 1878, and this site loads it through the 2025 season.

How a location is matched

The report first asks which perimeters contain the point. Every fire whose perimeter does is listed, most recent first, whatever its size or age. When none does, it looks for the nearest fire within 10 miles, measured to the edge of its perimeter, counting only named fires of 100 acres or more since 1950 so that the answer is one a reader can look up.

Limits of the record

The record is incomplete, most of all for older and smaller fires: about a quarter of the perimeters have no name or start date, and nearly half have no known cause. A perimeter is the outer edge of a fire, so it can enclose patches that did not burn, and each one is simplified to about 10 meters for this site. Where an area burned more than once, the perimeters overlap, and each fire is counted.

The California Department of Insurance collects every residential policy written by insurers with at least $10 million in California premium, and publishes the totals by ZIP code under Insurance Code section 929. This site loads its 2024 report, which covers the calendar years 2018 to 2023, and keeps only homeowners policies: renters, condominium, mobile home and landlord policies are left out.

How a location is matched

The Department reports by ZIP code, so the report finds the ZIP code around the location using the Census Bureau's ZIP Code Tabulation Areas. These follow the Postal Service's ZIP codes closely where people live, but they are drawn from census blocks, so near an edge the ZIP code shown can differ from the one on an address.

What is shown

The average premium is the premium the insurers earned in the ZIP code divided by the number of homes they insured over the year, counted in policy-years, so a home insured for half a year counts as half. Dividing it by the average amount the dwelling was insured for gives the premium for every $1,000 of coverage, which compares a costly home with a modest one more fairly. Each figure is set against the same figure for California.

The wildfire ratings come only from the insurers that reported a score for each home from their own commercial wildfire model, about two thirds of the policies. The Department converted each score to one of five categories, negligible, low, moderate, high and extreme, and the report shows the share of homes in each.

A ZIP code with fewer than 50 policy-years in the latest year is reported as having too few policies, because a handful of homes can swing an average far from what is typical.

Limits of the data

The figures leave out the California FAIR Plan, the insurer of last resort, and surplus lines insurers, which have both grown as regular insurers have pulled back from places at high risk of wildfire. Where many homes have moved to them, the regular-market average describes the homes that remain. The most recent year is revised in the Department's next report, published every two years.

The zone classes, power line tiers, fire records and insurance totals are each agency's own, unchanged. The sections above describe everything the site does with them: the zone overlap rule, the tiers left out, the simplified perimeters, and the averages calculated from the insurance totals. Beyond that, zone and tier shapes are cut into smaller pieces so a location can be looked up quickly, without moving their edges, and fire names and causes are reworded for display.

Check a result with the agency

Each report links to the agency's own map service for that exact point, so you can compare its answer with the report's in one click. To check any other point, use the services in the list with your own latitude and longitude.

For example, this query asks CAL FIRE's Local Responsibility Area map which zone contains a point in Malibu. Change the numbers after geometry= (longitude first, then latitude) to check another location.

For fire history, the service can confirm which perimeters contain a point. It can't check the nearest fire when none does, and within about 10 meters of a perimeter's edge the two may differ because of the simplification.

The insurance totals come from the Department of Insurance's published spreadsheet rather than a map service. Look up a ZIP code there to compare.

One known difference: Simi Valley and Thousand Oaks

In part of Simi Valley and Thousand Oaks, CAL FIRE's online Local Responsibility Area map returns two classes at the same point: Very High, and the Non-wildland, High or Moderate class around it. One Very High zone in CAL FIRE's online copy has lost the holes that should surround those areas. The downloadable package dated 24 March 2025, which this site uses, has the zones as drawn, so the report shows the class from the package.