Moon Phase Fishing Activity Calculator
Calculate fishing activity score based on moon phase and solunar theory.
Find the best fishing times using major and minor solunar periods.
How Moon Phase Affects Fishing
Lunar gravity affects tides, and tidal movement correlates with fish feeding activity. The strongest feeding periods align with major and minor lunar periods, as tracked by the Solunar Theory developed by John Alden Knight in 1926.
Solunar Period Timing:
- Major periods: When the moon is directly overhead (moon transit) or underfoot (opposite side of Earth), each lasts ~2 hours
- Minor periods: Moon rise and moon set, each lasts ~1 hour
- Total prime feeding time per day: approximately 6 hours across 4 periods
Moon Phase Rating for Fishing (1 to 10 scale):
These are the exact scores this calculator uses, not a range:
| Moon Phase | Score used | Notes |
|---|---|---|
| New Moon | 10 | Strongest tidal forces, best for inshore |
| Full Moon | 10 | Equal strong tidal pull |
| Waxing or Waning Crescent | 7 | Building or fading spring tide |
| Waxing or Waning Gibbous | 7 | Building or fading spring tide |
| First or Last Quarter | 6 | Neap tides, moderate activity |
Barometric pressure, and why it can outrank the moon:
| Pressure trend | Score used | What is happening |
|---|---|---|
| Falling slowly, front a day out | 9 | The classic feeding window, and it lasts |
| Falling fast, storm nearly overhead | 8 | Hard feeding, then it shuts off |
| Steady | 6 | Predictable, fish the solunar windows |
| Rising behind a front | 3 | The bluebird day nobody catches on |
A rising barometer after a cold front is the one condition that beats a new moon into the ground. The moon sets the schedule, but the weather decides whether anything shows up for it.
Best Fishing Windows: Major periods that coincide with dawn or dusk produce the highest catch rates. The solunar effect and the natural low-light feeding instinct stack, and that overlap is where the good days come from.
Tidal Connection (Saltwater):
Incoming tide + Major solunar period = Optimal fishing window
Moving water concentrates baitfish, which concentrate predators.
Practical Tips:
- New and full moon days: arrive 30 min before major period
- Log catches with moon phase over a season to find your local patterns
- A falling barometer ahead of a storm can override moon phase, and fish often feed heavily
- Species sensitivity varies: bass and crappie are highly solunar; catfish less so
How we build and check this calculator
This calculator runs entirely in your browser, so the numbers you enter stay on your device. The math behind it is written by hand and tested against worked examples and standard references before the page goes live.
SuperGlobalCalculator is independently built and maintained. See how we build and verify our calculators.