How the Strike Score Works: The 6 Factors Behind Every Surf Rating

The Strike Score is a single number from 0 to 100 that rates surf at one specific break on one specific day. It comes from six weighted factors: swell size, swell period, swell direction, wind, tide, and a spot-specific history adjustment. Here's exactly how we weigh each one, so you know what the number means before you trust it.

We don't rate the ocean in general, we rate your break against its own best conditions. A 6-foot swell that's perfect for a heavy reef would close out a mellow point, so every factor below is scored relative to what that particular spot needs to fire. Here they are, in the order they move the number.

1. Swell Size

Size sets the ceiling. We score it against the break's working range rather than in absolute terms, so a spot that lights up at 3 feet gets no bonus for 12, it gets marked down for closing out. Once size decides how good the day can be, the other five factors decide how much of that potential you actually get.

2. Swell Period

Period tells us how much energy the swell is carrying. Long-period groundswell of 13 seconds and up breaks with power and order, while short-period windswell breaks weak and messy. Two swells of identical height can score worlds apart once period is in the mix, which is why height-only forecasts mislead so often. Longer is better here, right up to the point a wave outgrows the spot.

3. Swell Direction

Every break has a swell window, the band of directions that actually reach it and switch it on. We compare the forecast direction against each spot's optimum and dock points for energy arriving off-angle. This is the biggest single reason two nearby breaks can read 90 and 40 on the same swell.

4. Wind

Wind decides whether good swell arrives clean or wrecked. Light offshore wind grooms and steepens the face and scores well, and onshore wind crumbles it and scores badly. Speed matters too, and the tolerance depends on the break. A sheltered slab falls apart above 25 km/h, a reef holds to around 35, and an open beach or point can take up to 40 before even offshore wind starts bumping the surface.

5. Tide

Many breaks only work through a specific slice of the tide. We check the forecast tide against each spot's known sweet spot, so a day with flawless swell and wind still loses points if the tide will back the wave off or shut it down while you're out there.

6. Spot-Specific History Adjustment

Finally, we correct for how each break actually behaves. Raw open-ocean model data can't see local bathymetry, refraction, or the small quirks that make real waves, so this adjustment nudges the score toward what the spot genuinely does rather than what the numbers predict in a vacuum. It also folds in recent wind history, because two clean days after a week of onshore slop groom a sandbank into something better.

Why the Top End Is Deliberately Hard to Reach

The score isn't linear at the top. We compress the 85-to-100 band on purpose, so only a genuinely flawless day reads in the mid-90s. That's why an Epic rating is rare and worth trusting. The full ladder runs Epic (95 to 100), Firing (80 to 94), Good (65 to 79), Fair (45 to 64), and Poor (0 to 44). When you see an 85, you're looking at a real day, not a generous one.

Why a Methodology Matters

A rating is only as good as the reasoning behind it. By scoring each break against its own ideal conditions and correcting for how it behaves in the real world, the Strike Score gives you a number you can act on instead of a wave-height readout dressed up as advice. Pull up any spot, tap the score, and you can see the factors that produced it.

Want to see it live? Check where it's firing right now, or read the nine forecast numbers that feed the score.

FAQ

What is the Strike Score?

A single number from 0 to 100 that rates surf at a specific break on a specific day, calculated from six weighted factors.

What factors does the Strike Score use?

Swell size, swell period, swell direction, wind, tide, and a spot-specific history adjustment that corrects for how each break actually behaves.

Why do two nearby breaks get different Strike Scores?

Mostly swell direction. Each break has its own swell window, so energy that lights up one spot can arrive off-angle and underwhelm the next.

Does the Strike Score just measure wave height?

No. Height sets the ceiling, but period, direction, wind, and tide decide how much of that potential is realized, which is why height-only forecasts are unreliable.