How to Measure the Beam of a Boat?

Last Updated on September 29, 2022

There are a few different ways that you can measure the beam of a boat. The most common way is to take measurements from the widest part of the hull, at the point where it meets the waterline. This is typically done with a tape measure and can be done from either side of the boat.

Another way to measure the beam is to take measurements from the deck at the widest point. 

This article will explore how to measure the beam of a boat using three different methods: water level, height gauge, and string line. We will also discuss the pros and cons of each method so that you can choose the right one for your needs. Happy boating!

Ship Basic Definition

  • To measure the beam of a boat, first, find the widest point of the hull.
  • Measure the distance from one side of the hull to the other at this point.
  • The beam of the boat is then simply this measurement.

What is the Beam of a Boat?

The beam of a boat is the width of the vessel at its widest point. This measurement is important for determining how many drafts the boat will have, as well as its overall stability. 

The wider the beam, the more stable the boat will be, but it will also require more depth to float. Narrower beams are less stable but can navigate in shallower waters.

Boat Measurements Explained

When it comes to boating, there are a few key measurements that you need to be aware of. 

Here is a quick guide to help you understand the most important boat measurements: 

Length Overall (LOA): This is the total length of the boat, from the tip of the bow to the stern. It is important to note that this measurement does not include any removable parts, such as swim platforms or bowsprits. 

Beam: This is the width of the boat at its widest point. For powerboats, the beam is typically measured at the midship section. Sailboats will often have their beam measured at different points depending on hull design. 

Draft: Draft refers to how deep your boat sits in the water. It is measured from the waterline to the bottom of your hull. If you have a shallow draft, it means your boat can operate in shallower waters without running aground. A deeper draft indicates that your vessel will require deeper waters to float safely.

Draft Measurement Boat

What is a Draft Measurement Boat? A draft measurement boat is a vessel that is used to measure the draft, or depth of water, of a ship. The boat is equipped with a sounding line, which is lowered into the water to measure the depth.

The sounding line is marked at regular intervals so that the depth can be read easily. The draft measurement boat first came into use in the early 1800s, and it was a vital tool for ships travelling in shallow waters. 

With the advent of sonar and other modern technologies, the draft measurement boat has become less essential, but it remains an important tool for measuring the depth of water in areas where sonar cannot be used effectively.

What is Draft on a Boat?

A draft is the depth of water a boat sits in. The deeper the draft, the more water the boat displaces and the higher it floats in the water. A boat’s draft also affects its stability; a shallower draft makes a vessel less stable than a deeper one.

How to Measure a Boat Width?

Whether you’re looking at different models in a showroom or trying to figure out if your current boat will fit in a particular slip, being able to accurately measure the width of a boat is essential knowledge for any boater. 

Here’s a step-by-step guide on how to do just that:

Step 1: Start by measuring from the widest point on each side of the hull. This is typically at the point where the hull meets the deck, but it could also be further back near the stern or bow. 

Step 2: Use a tape measure or ruler to extend straight out from each side until you hit the edge of the hull again. Make sure to keep the tape measure level as you go. 

Step 3: Write down both measurements and then take an average of the two numbers. This will give you the most accurate measurement of your boat’s width.

Step 4: Keep in mind that some boats have swim platforms or other protrusions that extend beyond the main hull body. If this is the case with your vessel, be sure to include these in your measurement so that you know exactly how wide your boat is overall.

Average Width of a Boat

Assuming you want the average width of a boat: The average width of a boat is about 8 feet. This can, of course, vary depending on the type and size of the boat.

For example, a small rowboat might be only 5 feet wide, while a large yacht could be up to 20 feet wide. So, 8 feet is just an average.

How to Measure the Beam of a Boat?

What’s the Beam Measurement on a Boat?

If you’re a boater, chances are you’ve heard the term “beam” used to describe a boat’s width. But what does beam actually mean? Simply put, the beam is the measurement of a boat’s width at its widest point.

This is generally at or near the middle of the vessel. The beam is an important measurement for a number of reasons. First and foremost, it affects a boat’s stability.

A wider beam means more stability, while a narrower beam means less stability. This is why pontoon boats and other wide-beamed vessels are often considered to be more stable than narrow-beamed vessels like canoes and kayaks. 

The wider the beam, the more weight the vessel can support without tipping over. This is why it’s important to know the beam measurement of your boat before loading it up with gear and heading out onto the water. 

So now that you know what beam is and why it matters, there’s just one question left to answer: what’s the typical beam measurement for different types of boats?

Well, that depends on the type of vessel in question. For example, small rowboats and dinghies typically have beams between 4 and 5 feet (1.2 to 1.5 meters). Larger sailboats and motor yachts, on the other hand, can have beams upwards of 15 feet (4.6 meters) or more!

As you can see, there’s no single answer to this question – it all depends on the size and type of boat in question. So next time someone asks you about your boat’s beam measurement, you’ll be able to give them an accurate answer!

How Do You Measure a Boat Beam And Draft?

There are a few different ways to measure the beam and draft of a boat. The most common way is to use a tape measure. To measure the beam, start at the widest point of the boat and measure from side to side.

To measure the draft, start at the waterline and measure down to the bottom of the hull. Another way to measure the beam and draft is by using a laser level. This method is more accurate than using a tape measure, but it requires special equipment that not everyone will have access to.

To use a laser level, set up the laser level so that it is perpendicular to the length of the boat. Then, place one end of the level at the stern (back) of the boat and hold it in place. 

Move forward until you reach the bow (front) of the boat and make a mark on the deck where the laser beam hits it. Measure from this mark to where the laser beam hits the deck at the stern, this is your boat’s length.


It’s important to know how to measure the beam of your boat if you’re planning on doing any type of sailing. The beam is the width of the boat at its widest point, and it’s a key measurement in determining both the stability and draft of the vessel. 

There are a few different ways that you can measure the beam of your boat, but the most accurate method is to use a tape measure.

Following the given simple guide, you’ll be able to accurately measure the beam of your boat so that you can properly assess its stability and draft!