How we score
Every half-hour of the coming week gets a score out of 100 for each fish, from the conditions fish respond to. Here's what goes in, where it comes from, and what we don't know yet.
What we weigh up
These five are weighed together, using each fish's own preferences:
- 40%Tide stageHow far into the flood or ebb. Each fish has favourite stages, when moving water stirs up food and lets it into the shallows.
- 25%Tide sizeSprings or neaps. Big tides move more water and colour it; some fish prefer the quieter neaps.
- 20%LightDawn, day, dusk or dark. Many sea fish feed hardest at dawn, dusk and after dark.
- 10%Sea stateWave height against what the fish likes: bass and cod like a bit of surf, sole and mullet prefer it calm.
- 5%Water temperatureWhether the sea is inside the fish's comfortable range.
These three can only lower a score:
- SeasonOut of season scores zero; early or late in the season is cut back.
- MoonAt night, the wrong moon takes up to 30% off for fish that care: bass, cod, whiting and sole prefer dark nights.
- WindStrong wind makes it harder to cast and spot bites, and costs more when it blows onshore.
What the numbers mean
An ordinary half-hour scores around 50 to 60. We spread the scale so only genuinely good times score highly: in a typical good week, only a few per cent of half-hours reach Excellent.
- Excellent 80+
- Good 65+
- Fair 50+
- Poor under 50
The best stretches are grouped into windows of up to three hours. Tap “Why?” on any window to see each reason and whether it's helping or holding the score back.
Where the data comes from
- TidesOfficial ADMIRALTY predictions where we have them, otherwise the Open-Meteo sea model, which can be up to an hour out in estuaries. The page says which it's using.
- Weather and seaOpen-Meteo forecasts for wind, gusts, waves and sea temperature, hour by hour.
- Sun and moonCalculated for the exact spot: sunrise, sunset, twilight and how much moon is lit.
- Fish behaviourSpecies profiles built from FishBase, the Cefas Catchwise survey of UK sea anglers (for when each fish is caught), and UK angling guidance.
- Which fish are at a markMeasured depth and seabed (EMODnet), shore type (OpenStreetMap), Environment Agency fish surveys and club match catches, rated by an AI model and checked against local anglers' answers.
What we don't know yet
- The species profiles are drafts. We're still checking each one against published studies.
- Tide times from the sea model are approximate, especially up estuaries.
- Air pressure isn't scored. The evidence that it changes how fish feed is weak.
- The score says when to go, not how good a mark is. A pier into deep water can out-fish a shallow beach on the same tide, and we're gathering match results to measure that.
- Local anglers' answers are shown next to the science, never mixed into the score.
- Sponsors never change a score, a fish rating or which marks we show. Sponsor cards are always labelled.
How it gets better
We test the scores against real catches: club match results, where everyone's fish are counted over set hours, and later anglers' own catch logs. When the catches disagree with the science, the science changes.