2 min read · Updated 22 June 2026
Sailboats are grouped in three overlapping ways: by hull, by size and purpose, and by rig. A given boat is described by all three at once — for example, a "monohull sloop keelboat". Understanding these three axes is the quickest way to make sense of the huge variety of sailing boats, from a two-metre learner's dinghy to a hundred-foot supermaxi.
By hull: monohull or multihull
The most fundamental split is how many hulls a boat has:
- Monohull — one hull, kept upright by a ballasted keel (or, on a dinghy, by the crew). The classic yacht shape.
- Multihull — more than one hull: a catamaran has two, a trimaran has three. They get their stability from width rather than ballast, which makes them faster and flatter-sailing.
The trade-offs between the two are covered in monohull vs multihull.
By size and purpose
Within monohulls especially, boats are described by what they are for:
- Dinghy — a small, light boat with no fixed keel, kept upright by crew weight; it can capsize. Ideal for learning and hands-on sailing.
- Keelboat — larger, with a heavy ballasted keel that keeps it upright. The basis of club racing, cruising and offshore sailing.
- Cruiser — built for comfort and distance, with accommodation and easy handling.
- Racer — built for speed: light, stiff and powerful, with few comforts. Many boats are cruiser-racers, splitting the difference.
- Sportsboat — a small-to-medium keelboat built to plane and sail fast, bringing dinghy-style thrills to keelboat racing.
- Trailer-sailer — a small keelboat light enough to tow behind a car.
- Maxi and supermaxi — the giants of the sport, the largest racing yachts.
By rig
The third axis is the rig — the arrangement of masts and sails. The most common is the sloop (one mast, a mainsail and a single headsail), but there are several others: cutter, ketch, yawl, schooner and more. Because the rig is a whole subject in itself, it has its own guide: types of sailing rigs.
Putting it together
Every sailboat sits somewhere on all three axes. The Melges 40 that this campaign races, for instance, is a monohull (one hull), a sportsboat / racing keelboat by purpose, and a sloop by rig — a high-performance one-design built for grand-prix racing. Learn to read those three labels and you can place almost any boat you see on the water. For the terminology, see the sailing terms glossary.
Frequently asked questions
- What are the main types of sailboats?
- Sailboats are classified in three overlapping ways: by hull — monohull (one hull) or multihull (a catamaran with two, or a trimaran with three); by size and purpose — from small dinghies to keelboats, cruisers, racing yachts and sportsboats; and by rig, the arrangement of masts and sails, such as sloop, cutter, ketch, yawl and schooner. Any given boat is described by all three.
- What is the difference between a dinghy and a keelboat?
- A dinghy is a small, light boat with no fixed ballast keel — it is kept upright by the crew's weight and can capsize. A keelboat is larger and has a heavy ballasted keel underneath that keeps it upright and stops it capsizing in normal conditions. Dinghies are ideal for learning and hands-on sailing; keelboats are used for club racing, cruising and offshore sailing.
- What is a sportsboat?
- A sportsboat is a small-to-medium keelboat built for high performance — light, powerful and designed to plane and sail fast, usually with an asymmetric spinnaker flown from a bowsprit. Sportsboats bring dinghy-style excitement to keelboat racing, and the type spans from small trailerable boats up to Grand Prix one-designs.
- What is the difference between a cruiser and a racer?
- A cruising sailboat is built for comfort and easy handling over distance, with accommodation below and a rig that is simple to manage. A racing sailboat is built for speed, with a light, stiff structure, a powerful rig and minimal comforts. Many boats are cruiser-racers, a compromise that can do club racing on the weekend and cruise on the holidays.
- Are catamarans sailboats?
- Yes. A catamaran is a type of sailboat with two hulls, and a trimaran has three — both are multihulls. They gain stability from their width rather than a ballasted keel, which makes them faster and flatter-sailing than monohulls, though they do not self-right if capsized. Multihulls are used for both cruising and racing.