We have become obsessed with measuring yachts in metres. Yet length alone tells us remarkably little about the yacht we are actually buying, chartering or stepping aboard.

I remember when I first started studying yacht brokerage, one of the things that became increasingly obvious was just how misleading the basic numbers could be. We naturally want an easy way of comparing one yacht with another, and length gives us one. A 60-metre yacht is bigger than a 50-metre yacht. That seems simple enough.

Except it really isn't.

Spend any time looking closely at yachts and you soon discover that two vessels carrying exactly the same length on their specifications can feel as though they belong to completely different classes.

One 60-metre yacht might feel relatively intimate, with elegant lines, modest interior volume and beautifully proportioned exterior decks. Step aboard another 60-metre yacht and you can find enormous salons, a substantial owner's apartment, a beach club, gym, cinema, extensive crew accommodation and enough storage for a small fleet of tenders and toys.

They are both 60 metres long.

So what has happened?

The answer is that we have been measuring the easiest dimension rather than necessarily the most useful one.

Length overall — usually shown as LOA — tells us the distance from one end of the yacht to the other. It is important. It affects berthing, regulations, design and numerous practical considerations. But it doesn't tell us how much yacht exists between those two points.

That is where things become much more interesting.

I sometimes think cars provide a useful comparison. Two cars can have roughly the same length, yet one is a low two-seat sports car and the other a tall SUV carrying seven people and their luggage. Nobody would seriously suggest that they provide the same amount of usable space simply because their bumpers are a similar distance apart.

Yachts are no different.

Beam — the yacht's width — begins to change the picture immediately. Add more beam and the designer suddenly has considerably more floor area to work with. Add height and additional decks, and the available volume grows again. Change the shape of the hull and superstructure and it changes further.

This is why I increasingly look at gross tonnage when trying to understand what a large yacht actually represents.

Despite the name, gross tonnage is not simply the yacht's weight. In this context it is fundamentally a measure derived from the enclosed internal volume of the vessel. For somebody trying to understand why one yacht feels so much larger than another of similar length, that can be a far more revealing number.

You can see the difference the moment you step aboard.

On one yacht, the main saloon may be beautifully designed but relatively conventional. On another of similar length, the same area can feel more like the lobby of a private residence. Corridors are wider. Staircases become architectural features. Ceiling heights increase. Guest cabins grow. The owner's suite expands from a bedroom into a genuine private apartment.

Then somebody opens another door and there is a cinema.

That extra volume has to come from somewhere.

It is one reason I would never advise somebody to judge a yacht simply by saying, “I want something around 60 metres.”

My next question would be: what sort of 60 metres?

Do you want something sleek and elegant that slips relatively easily into established Mediterranean harbours? Do you want enormous interior volume? Do you want large exterior decks? Do you need substantial tender storage? Are you carrying twelve guests or is much of the yacht primarily for one family? Do you want a full-beam owner's deck? A large spa? A helicopter? A serious gym? An enormous beach club?

The answers begin defining the yacht far more effectively than its length.

There has also been a noticeable change in what owners expect from the stern of a yacht. Years ago, the aft end was largely an attractive place to sit and perhaps access a swimming platform. Today it can be one of the most complicated areas of the entire vessel.

The modern beach club has completely changed yacht design.

What used to be machinery, tender storage or technical space can now become an extraordinary waterside environment. Side terraces fold down. Stern doors open. Pools appear. Gyms overlook the sea. Treatment rooms, bars, saunas and lounges sit almost at water level.

It looks spectacular, but there is no free space aboard a yacht. If we create a huge beach club, something else has to move or the yacht has to gain volume.

That is the part of yacht design I find fascinating. Every impressive feature creates another problem for the designer and naval architect to solve.

Put the tenders somewhere else.

Move the machinery.

Find more crew circulation.

Create storage.

Maintain structural integrity.

Keep the yacht balanced.

Preserve the exterior profile.

And somehow make the guest believe none of this was difficult.

The owner may simply see a beautiful room opening onto the sea. Behind the walls is an enormous exercise in compromise.

The same applies at the other end of the yacht.

A near-vertical bow can create a very different internal arrangement from a long, sweeping traditional bow. Different hull forms use the available length differently. An explorer-style yacht may carry its volume much further forward and higher than a low-profile yacht designed primarily around elegance and speed.

Neither approach is automatically better.

They are simply trying to achieve different things.

I think this is where yacht design becomes much more personal than people initially realise. There is no mathematically perfect yacht because owners do not all want the same life aboard.

One owner might happily sacrifice internal volume for beautiful exterior proportions and performance. Another may want the maximum possible living space within a particular length because berth availability matters. Another wants huge open decks because the yacht will spend most of its life in warm climates. Another wants protected interior observation spaces because the yacht is going north.

The yacht begins to reflect the programme.

Crew requirements make another enormous difference, although guests rarely notice them.

Every guest space aboard a large yacht is supported by another world behind it.

There are crew corridors, staircases, pantries, galleys, laundries, stores, mess areas, cabins, technical spaces and service routes. On a well-designed yacht, guests may barely see any of this.

That is deliberate.

Imagine dinner for twelve guests on the upper deck. Food needs to travel from the galley to the table at the correct temperature. Plates have to return. Drinks need replenishing. Crew need to move in and out without repeatedly crossing guest areas.

Now imagine doing that several times a day for weeks.

A yacht with generous crew circulation may therefore operate completely differently from another yacht of identical length where those spaces have been compressed to create another metre of guest accommodation.

You might never spot the difference during a ten-minute viewing.

You could certainly notice it after living aboard for a month.

Storage is similar.

Storage is not particularly exciting at a yacht show. Nobody proudly photographs a cupboard full of spare filters.

But start using a yacht properly and storage becomes enormously important.

Where does the luggage go?

Where are the provisions?

Where are the spare parts?

Where is the wine?

Where are the water toys?

Where are the diving cylinders?

Where are the deck cushions when the weather changes?

Where are the crew uniforms, cleaning products, linen, engineering supplies and everything else required to make this floating private residence function?

A yacht designed for long-distance cruising may devote a surprising amount of its volume to things the owner never sees.

That is not wasted space.

It is what allows the visible spaces to work.

Then we have machinery.

This is another reason yachts of apparently similar dimensions can be so different.

A high-performance yacht designed to travel quickly has very different engineering requirements from a displacement yacht intended to cruise efficiently over long distances. Engines, fuel capacity, exhaust systems, ventilation, generators and supporting machinery all consume space.

Speed is never free.

It costs fuel, engineering space and, frequently, volume that might otherwise have become accommodation.

This is why I think asking for the maximum speed of a yacht without understanding how the owner intends to use it can be slightly meaningless. If somebody spends almost all their time cruising slowly between Mediterranean anchorages, designing the entire vessel around a top speed they will rarely use may involve compromises elsewhere.

The best yacht is not necessarily the yacht that can do the most.

It is the yacht that does what its owner actually needs exceptionally well.

And this is where the numbers on brokerage listings need interpretation rather than simply comparison.

Length.

Beam.

Draft.

Gross tonnage.

Range.

Speed.

Guest numbers.

Crew numbers.

They are clues.

Taken individually, they tell us very little. Put them together and a picture begins to emerge.

A wide, high-volume yacht with substantial gross tonnage relative to its length is telling us something. A narrow, sleek yacht with powerful machinery and higher speed is telling us something completely different. An explorer with enormous fuel capacity, large stores and substantial technical spaces tells another story again.

The specifications are effectively describing the personality of the yacht before we have even walked aboard.

Age complicates matters further.

A modern 60-metre yacht may have been designed around expectations that barely existed when an older yacht of the same length was launched.

Owners now routinely expect levels of connectivity, entertainment, wellness and watersports capability that would once have seemed extraordinary.

The modern yacht may need space for large server installations, sophisticated AV systems, battery banks, treatment rooms, gyms, bigger tenders and far more toys.

Yet older yachts can have advantages of their own.

Some were built with extraordinarily generous machinery spaces. Others have layouts and proportions that would be difficult to reproduce today. A major refit can combine much of that original character with modern technology.

This is one of the reasons I would never dismiss a yacht simply because of its age.

I would rather understand how it was built, how it has been maintained and what has happened to it since.

Refits can also fundamentally alter the way a yacht works.

A yacht may leave the shipyard one way and, fifteen years later, bear surprisingly little resemblance to its original configuration. Interiors change. Decks are extended. Beach clubs are created. Tenders move. Technology is replaced. Machinery is upgraded.

Sometimes even the length changes.

So when looking at a yacht's basic specification, I want to know the story behind the numbers.

That story becomes especially important when buying.

I can understand why somebody beginning a yacht search might say, “Show me yachts between 50 and 55 metres.”

It creates a manageable starting point.

But I would not want the search to remain there.

If a 57-metre yacht provides exactly the accommodation, capability and operational profile the buyer needs, rejecting it because somebody originally typed “55 metres maximum” into a search box makes little sense unless there is a genuine operational reason for that limit.

Equally, a 52-metre yacht may provide substantially more usable space than another yacht several metres longer.

This is where an experienced broker should move beyond simply forwarding listings.

The job is not merely to find yachts matching a number.

It is to understand what the client is trying to achieve and recognise which yachts deliver it.

Sometimes the yacht that looks wrong on paper becomes the obvious choice when you step aboard.

And sometimes the opposite happens.

A yacht can have spectacular photographs, the correct length, the right builder and an impressive specification, yet the moment you walk through it something simply does not work for that particular buyer.

Perhaps the owner's suite is wrong.

Perhaps the exterior spaces are too small.

Perhaps the crew circulation is compromised.

Perhaps the tender arrangement does not suit them.

Perhaps it simply feels smaller than expected.

That last word — feels — matters more than we sometimes acknowledge.

Yachts are emotional purchases.

People do not experience gross tonnage.

They experience space.

They notice whether a room feels open or enclosed. Whether they can see the sea. Whether the ceiling feels high. Whether there is privacy. Whether twelve people can sit together comfortably without feeling as though they are in a conference room.

Designers manipulate that perception brilliantly.

Glass can make a room feel larger.

Long sightlines can connect spaces.

Open staircases can create volume.

Sliding doors can merge interior and exterior areas.

Furniture placement can completely alter the apparent scale of a room.

Two yachts with similar physical volume can therefore still feel very different.

And then there is exterior space.

I think this is sometimes overlooked because gross tonnage naturally focuses attention on enclosed volume.

For many owners, however, the reason for owning a yacht is to be outside.

They want breakfast on deck, afternoons around the pool, dinner beneath the stars and easy access to the sea.

A yacht that sacrifices some interior volume for exceptional exterior decks may therefore be far better for them than a much larger-volume yacht of exactly the same length.

There is no winning specification.

There is only suitability.

That is probably the biggest lesson I took from studying yacht brokerage and subsequently looking at yachts with a more analytical eye. The specification sheet is the beginning of understanding a yacht, not the conclusion.

It tells me enough to know what questions I want to ask.

Why is the gross tonnage unusually high?

Where has that volume gone?

Why is the beam relatively narrow?

What has been prioritised?

How much space has been given to crew?

Where are the tenders?

How much storage is there?

What is beneath the guest areas?

How is the yacht actually intended to be used?

Once you start asking those questions, yachts become much more interesting.

You stop seeing them simply as a row of lengths in a brokerage database and start seeing the decisions that created them.

Every yacht is a collection of compromises.

More speed may mean more machinery and fuel.

More interior volume may change the exterior proportions.

A larger beach club consumes space somewhere.

Bigger tenders need storage.

More guests require more crew.

Longer range requires fuel and provisions.

Helicopters need infrastructure.

Submersibles need handling equipment.

Nothing happens in isolation.

Perhaps that is why I am increasingly reluctant to describe yachts primarily by their length.

Of course I still do it. Everyone in the industry does. It is convenient, and it immediately gives some sense of scale.

But it is only the first line of the story.

If somebody tells me they have seen two 60-metre yachts and cannot understand why one feels vastly larger than the other, there is nothing unusual about it.

They may have been looking at two completely different ideas that happen to occupy the same distance from bow to stern.

One might have been designed to be fast, elegant and relatively intimate.

The other might have been designed as a high-volume floating residence.

A third could be a long-range explorer carrying enormous quantities of fuel, equipment and stores.

A fourth might be optimised around charter.

All 60 metres.

All superyachts.

All completely different.

And that is why, if I were buying one, I would never begin by asking:

“How many metres can I get?”

I would begin with a much more useful question.

“How do I want to live aboard?”

Once you know the answer to that, the numbers finally start to mean something.

About the Author

Paul Thompson holds a Diploma in Yacht Brokerage and has a long-standing background in sales, marketing, digital publishing and the international yachting sector. He is a yachting journalist and publisher of Superyacht Magazine.

This article is intended as general editorial information. Yacht dimensions, tonnage measurements, regulatory thresholds, design characteristics and operating requirements vary between vessels and jurisdictions. Buyers should rely on the vessel's official documentation and appropriate professional, technical and regulatory advice when evaluating a yacht.