About

About the numbers

FleaDates is informative math on top of public data — never diagnosis, dosing, or a substitute for your vet. Here's exactly where everything comes from.

The season estimates

Every flea and tick season on this site is a climate-based estimate. We start from the NOAA U.S. Climate Normals, monthly temperature (1991–2020) — the official 30-year monthly temperature averages from NOAA weather stations near each state's larger cities (NOAA data is public domain). Onto that we apply activity thresholds from published veterinary and entomology research: fleas reproduce actively outdoors once averages hold around 50°F and thrive between 65–80°F; many ticks quest above roughly 40°F. Where the temperature curve crosses a threshold, a season begins or ends — nudged a week earlier at the start and a week later at the end, because when we round, we round toward caution.

Two honest limits. First, these are 30-year averages: any single year runs early or late with the weather. Second, they describe outdoor pressure — indoor fleas are year-round everywhere, and veterinary organizations recommend parasite prevention all twelve months. Nothing on this site should be read as permission to skip winter doses.

For live parasite prevalence tracking (a different thing from climate seasonality), the Companion Animal Parasite Council's maps are worth a look: capcvet.org/maps. We don't reproduce their data here.

The calculators

The dog-owner calculators use the standard published formulas, encoded conservatively — chocolate math rounds the toxin content up, portion math leads with the low end of feeding ranges, and every result points to your vet for the real decision. The references:

Who this is for

Dog people who like a straight answer: when does flea season actually start here, how much should the dog eat, is that fun-size bar a problem. The answers are honest about being estimates, and the emergencies are treated like emergencies — the chocolate page keeps the ASPCA poison-control number front and center and always will.