What is solunar theory?

Solunar theory, developed by John Alden Knight in 1926, proposes that fish and wildlife are most active during specific periods influenced by the position of the sun and moon. Major periods occur when the moon is directly overhead or underfoot; minor periods occur at moonrise and moonset.

What are major and minor fishing periods?

Major periods last roughly 2 hours and occur when the moon is at its zenith (directly overhead) or nadir (directly underfoot). Minor periods last about 1 hour and coincide with moonrise and moonset. Activity is typically highest during major periods near a new or full moon.

Does moon phase affect fishing?

Many anglers and researchers note that fish tend to feed more actively during new and full moon phases, when tidal forces are strongest. The gravitational pull affects not just ocean tides but also lake and river currents, triggering baitfish movement and feeding behavior.

How accurate are the times shown?

Times use a simplified lunar-position model and assume your civil time zone is reasonably aligned with local solar longitude. They are planning estimates, not precise ephemeris or tide predictions. Longitude, latitude, daylight-saving boundaries, and local geography can shift real events; verify against a local tide chart.

Why are there no tide heights shown?

Actual tide heights depend on local geography (bay shape, depth, coastline) and require real-time NOAA or local authority data. This tool focuses on the solunar component — moon-phase-driven feeding activity — which applies equally to freshwater and saltwater fishing.

What does the fishing activity score mean?

The phase-only score ranges from 40 at quarter moons to 100 at new/full moons. It is a solunar indicator, not a prediction of catch success; weather, water, season, and local conditions matter more.

Tide Fishing Planner

Pick a date to see the moon phase, solunar major and minor fishing windows, and an overall fishing activity score — no login or API key needed.

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Date

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Your solunar peak fishing windows will appear here.

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Summary

The Tide Fishing Planner calculates the astronomical solunar component of tidal trip planning using moon phase and lunar position math. Enter a date to see peak feeding windows, major and minor periods, and an overall fishing activity score right in your browser.

How it works

The tool calculates the Julian date for your selected calendar date.
A lunar phase algorithm (based on Meeus astronomical algorithms) determines the moon age and phase name.
Lunar transit times (overhead and underfoot) are computed from the moon's hour angle, defining major solunar windows.
Moonrise and moonset times define the two minor solunar windows.
A fishing activity score is derived from moon phase proximity to new/full moon and the quality of daily windows.

Use cases

Plan a freshwater bass fishing trip around peak solunar windows.
Identify which days this month have the highest fishing activity scores.
Check whether a full or new moon coincides with your weekend trip.
Schedule early-morning or late-evening outings during major feeding periods.
Teach new anglers about the solunar theory and lunar fishing calendars.

Frequently Asked Questions

Last updated: 2026-06-11 · Reviewed by Nham Vu

Tide Fishing Planner

Select a Date

Moon Phase

Fishing Activity Score

Solunar Feeding Windows

24-Hour Activity Timeline

About Solunar Theory

Summary

How it works

Use cases

Frequently Asked Questions

Tide Fishing Planner

Use the Tide Fishing Planner

Select a Date

Moon Phase

Fishing Activity Score

Solunar Feeding Windows

24-Hour Activity Timeline

About Solunar Theory

Summary

How it works

Use cases

Frequently Asked Questions