Bitespan is a free freshwater fishing forecast service that helps anglers choose when and where to fish. It uses live National Weather Service data and species-specific feeding models to create hour-by-hour bite forecasts for lakes across the United States, currently covering walleye and bass. Anglers can select a lake, species, and date within the next seven days, then view scores ranging from Poor to Excellent, with the day’s peak bite window highlighted.

Each score breaks down five contributing factors, including weather conditions and species preferences for temperature, light, wind, and pressure. Bitespan also displays solunar periods but clearly identifies them as unsupported by testing, allowing users to weigh that information appropriately. Forecast precision is limited to the reliable data horizon: the service provides hourly scores when available, broader estimates beyond it, and no forecast when evidence is insufficient.

A seven-day calendar supports comparisons between lakes and species. Bitespan is designed for bank, kayak, and boat anglers, and requires no account, app, or email to use.