Learning How to Measure Waves When Surfing


If you’re new to surfing, or even if you have some surfing experience, learning how to measure waves when surfing can be one of the biggest challenges, but one that’s very important to master. The only true way you can read waves is to interact, study, and watch waves. Over time, you’ll get the hang of accurately gauging the wave height, but in the beginning, when life on a board is totally new, it can be frustrating and difficult to predict and measure them. This guide can walk you through what you need to know and the tips and tricks that you can use that will help you accurately measure waves the next time you’re in the water.

The Anatomy of a Wave

A surfer doesn’t need much when they’re in the water, just the best surfing wetsuit, a good board, and knowledge about waves.

Waves are moving energy and they don’t transfer the water; they simply move through the water. This means that waves aren’t a traveling bump of water. The bump you see approaching the shore is basically energy that’s traveling through the water. Not all waves are the same. Some are very weak with little energy, while others carry a lot of energy and are very powerful.

The energy of a wave is measured in three dimensions. When you’re first learning how to read a wave, it’s important to take these dimensions into account, don’t just focus on the height of a wave. Since you’ll be spending so much time in the water observing waves and learning how to measure them, make sure you wear the appropriate type of suit based on environment, water temperature, and air temperature. To learn more, click here to read my guide on the advantages and disadvantages of surfing in a wetsuit.

How Waves are Measured

Ocean Wave

A wave is measured similarly to how volume is calculated via multiple dimensions. A wave is measured in the interval, direction, and their height.

Height is measured in meters or feet; swell interval is measured based on how many seconds it will take two peaks of energy to surpass a buoy.

The more you know about why and how waves change their break and shape, the better you’ll be able to use the fundamental skills in order to position yourself in the water to ride them.

The beginner must understand how far out a wave breaks from the shore, what type of shape it’ll make once it breaks, and how fast will the sections of the wave break down.

These three things will determine where a surfer needs to be in the water in order to catch a good wave, how they can anticipate whether or not to take off on the wave they’ve caught, and the angle they should approach the wave.

If you’re new to surfing, then click here to read my guide on surfing tips for beginners to learn more about the fundamentals of surfing.


So, why do some waves tend to break far out while others break close to shore? Learning why waves break in the first place is a good place to begin.

A wave will break because they grow too unstable and tall to withstand gravity. Keep in mind that waves are essentially energy that travels under the water. As the energy reaches the shore the water becomes very shallow. The energy will start to feel the floor of the ocean. Since the floor slopes upward toward the shore, it pushes the energy above sea level. When a wave proceeds to get taller until it breaks, you’re witnessing the effects of traveling energy that’s being pushed up as the floor rises closer to the water’s surface.

Catching Waves

A wave often makes a last reach to the sky before it starts to break. A sandbar or reef is usually what gives the energy a final push against gravity. This is the moment that the wave has grown too tall for its own support and that’s when it breaks.

Every wave and surfing spot the wave interacts with is different. Because of this, the time that the waves will break will also be different.

Additionally, the more you know about the sea floor of your usual spot, the better you will be able to position yourself ahead of time in order to catch a wave. If you usually surf where the sea’s floor’s shape hardly changes then this will be especially important.

A surfer wants to paddle just far enough past the breaking point of a wave. What they’re doing is positioning themselves where the water’s too deep for a wave to break. They will want to remain close to the reef where the wave breaks so that they’re able to paddle and catch it before it breaks.

Since every wave is different, they will hit the reed or sand bar slightly differently. This is why waves that are part of the same swell can break at different distances from the shore or reef.

Because of this, the position of the surfer in the water shouldn’t be stationary. Instead, they must paddle constantly based on what they have read in every wave.

The ability to position themselves correctly on that dynamic and fine line between where it doesn’t break and where it does is one of the first skills a surfer will need to cultivate.

Since each wave in a swell possesses different levels of energy, the fine line between caught and safely outside the impact zone is always shifting.

So, what can help a surfer to stay in position?

How Beginners Can Catch a Wave

Female surfboarder

A wave that develops and breaks slowly will be perfect for the beginner. When the wave reaches the height where they break, they will spill over gently, creating a relaxed breaking wave. A surfer will usually refer to this type of wave as mushy. A mushy wave is perfect for beginners who are new to catching waves. They’re less consequential, not steep, soft, and slow.

For a beginner, a bad wave is one that breaks and grows quickly. Instead of spilling, these waves have a crest that pitches out through the air toward the shore, creating a concave round wave face as the lip impacts the trough. A wave that will break and pitch top to bottom will be concave, powerful, and fast, which is what makes them such a bad choice for beginners. The surfer will only have a very small window to pop up, with the consequence of having bad timing will be much higher compared to a mushy wave. Keep in mind, a wave will break because it’s in water that’s too shallow.

How quickly a wave will break is all due to the rate that the ocean floor rises up to the shore. A good spot for a beginner will usually have a slow long slope from the sea to the shore, similar to a boat ramp that will descend gradually into deep water.

Challenging waves will approach the shore in deeper water until it enters shallow water suddenly. This type of abrupt depth change will cause the wave to pop up lurching quickly, causing them to become unstable rapidly, which will lead to a powerful and faster break. If the waves gradually slow down, like when a wave approaches a slowly inclining floor, it will break slowly. However, if the wave travels in deep water and hits shallow water suddenly, then it will quickly become steep and concave as it breaks.

This information can help you to better understand the sea floor at your local surfing spot, which can help you learn how to read the waves better and make the right decision about how and where you can surf.

Final Thoughts

As a new surfer, there’s so much to learn, but practicing measuring waves is a skill that you’ll find yourself relying on throughout the years, for as long as you surf. It’s a skill that can take months or years to develop, depending on how observant you are and how much time you spend in the water.

Learning how to measure waves when surfing will allow you to choose the right wave for you, based on your surfing skills. It can also help you determine whether or not a wave will be dangerous, before you attempt to catch it and how to correctly position yourself in the water in order to catch a good wave. The best way to learn how to read waves and measure them by sight alone is to get out there at your local surfing spot and practice the techniques I’ve included in this guide. With practice and patience, you’ll soon learn how to find the perfect wave and position yourself in the water correctly in order to catch it.