Ocean Alexander 100
The Ocean Alexander 100 is the largest platform in the core Ocean Alexander semi-displacement lineup and one of the most deliberately engineered 100-foot motor yachts in production history. Built in limited numbers over a production run that ended with hull number 18, it occupies a specific position in the used market: narrow supply, an experienced buyer pool and a price range that demands precise market knowledge from anyone on either side of the transaction. This page covers the platform specifications, design architecture and the key distinctions buyers and sellers need to understand before engaging the market.
Two Generations
The Ocean Alexander 100 spans two distinct generations. The 2008 build, designed by Ed Monk, carries a 22-foot beam, twin MTU 10V 2000 engines at 1,502 horsepower each and a traditional interior architecture appropriate to its era. Beginning in 2016, Ocean Alexander introduced a comprehensively redesigned platform with a 23-foot beam, twin MTU 12V 2000 engines at 1,920 horsepower each, the Evan K. Marshall interior and a structural engineering package that includes marine-grade aluminum beam construction and the Sylomer floating floor system. These are not cosmetic differences. The 2016-and-later build is the platform this page references unless noted otherwise. For a detailed breakdown of how the two generations affect current market pricing, see the Ocean Alexander 100 current market guide.
Platform Architecture
The aluminum beam engineering that defines the 2016-and-later 100 is the most consequential structural decision in the platform’s design. Marine-grade aluminum beams replace conventional fiberglass in floors, walls and ceilings, providing a rigidity that reduces movement and eliminates the low-frequency resonance common in fiberglass construction at this length. The practical result is a quieter, more stable interior environment underway. The same engineering enables window spans that would not be structurally achievable in conventional construction at 100 feet, which is why the 100 Skylounge’s panoramic glass lines are possible without compromise to hull integrity.
The Sylomer floating floor system, which Ocean Alexander notes is typically a feature of vessels 130 feet and larger, is standard throughout the 2016-and-later build. Combined with multiple insulation barriers using reflective, absorptive and dampening materials, the noise and vibration levels on the 100 consistently test at a fraction of ISO-6954 requirements. Owners who have operated other yachts in this length range before stepping into a 100 comment on the difference within the first passage.
The hull is vinylester resin with high-density structural foam, providing thermal and acoustic insulation advantages alongside the structural benefits. The exterior is finished in Alexseal polyurethane paint with epoxy-based primers, which Ocean Alexander specifies as standard rather than an option. Cross-knit directional carbon fiber reinforces high-stress areas for added torsional strength.
Layout and Accommodation
The 100 is available in two upper deck configurations. The Skylounge version adds an enclosed second salon above the main deck with panoramic windows on all four sides, a dedicated helm station, wet bar and aft deck access through electric sliding glass doors. The Flybridge configuration positions the upper helm and entertainment area in a more open format with a traditional bridge deck layout including, on some examples, a four-person Jacuzzi aft.
The five-stateroom layout with an on-deck master suite is the most common configuration in current inventory and the one most buyers in this market are seeking. The on-deck master is full beam with wraparound windows, a king berth, walk-in closet and a private ensuite featuring heated stone floors and a marble shower. Four guest staterooms occupy the lower deck in the standard arrangement: two queen cabins to port and starboard and two twin cabins forward that slide together to form a queen. All staterooms carry private ensuites.
Crew quarters are located aft on the lower deck with a separate watertight access point from the swim platform, keeping crew movement fully separated from guest areas. The crew area accommodates three to four crew members and includes a captain’s cabin with private ensuite, crew lounge with galley and a dedicated work area with stainless steel workbench.
The galley is positioned on the main deck forward of the salon, typically with Sub-Zero refrigeration, Thermador cooking equipment and stone countertops throughout. The Evan K. Marshall salon furniture is custom-designed for each build, with concealed storage integrated into settees and cabinetry.
Propulsion and Systems
The 2016-and-later 100 is powered by twin MTU 12V 2000 engines producing 1,920 horsepower each, driving through ZF transmissions to NiBrAl high-performance propellers on Aqua 22HS shafts. Twin Kohler 55 kW generators provide ship’s power. The Atlas 50/60 Hz power converter is standard, allowing connection to both US and European shore power without modification.
Sidepower Vector Fin 15-foot hydraulic stabilizers with zero-speed stabilization are present on most 2016-and-later examples as either standard or a major option. The stabilizer system takes power off from both engines to provide redundancy, a feature Ocean Alexander notes is not standard on competing platforms. Bow and stern thrusters are standard at 55 HP and 40 HP respectively.
The dual Sea Recovery watermakers at 1,400 gallons per day each, the Gulfcoast fuel polishing system and the lube oil change system with a 45-gallon tank are standard features that on competing platforms are either options or not available at this length. The engine room air conditioning, dry bilge ventilation system and color-coded piping are part of the same design philosophy: reduce ownership friction on extended passages.
Navigation is centered on the Garmin 8600 series black box system with multiple 24-inch touchscreen displays at the skylounge helm, dual 25 kW open array radar, Garmin autopilot, AIS and full N2KView safety and monitoring integration. Starlink is present on most 2017-and-later examples.
Confirmed Specifications: 2016 to 2020 Generation
| LOA | 100 ft 8 in (30.71 m) |
| Beam | 23 ft (7.01 m) |
| Min Draft | 5 ft 6 in (1.68 m) |
| Max Draft | 6 ft 5 in (1.96 m) |
| Displacement | 220,264 lbs |
| Fuel Capacity | 4,000 gallons |
| Fresh Water | 650 gallons |
| Holding | 400 gallons |
| Main Engines | Twin MTU 12V 2000, 1,920 HP each |
| Generators | Twin Kohler 55 kW |
| Cruising Speed | 18 to 19 knots |
| Max Speed | 22 to 24 knots |
| Range | Approximately 564 miles at cruise |
| Staterooms | 4 or 5 (on-deck master on 5-stateroom layout) |
| Crew Cabins | 3 |
| Gross Tonnage | 200 to 208 GT |
| Hull Construction | Vinylester resin with high-density structural foam |
| Interior Designer | Evan K. Marshall (2016 onward) |
What This Platform Means in the Used Market
The Ocean Alexander 100 was built in 18 total hulls. That number is not a limitation of the builder. It is the result of a deliberate production philosophy. When a qualified buyer is evaluating used 100-foot semi-displacement motor yachts in the $5,000,000 to $9,000,000 range, they are working through a known list of specific boats rather than a broad category. Every hull is traceable. Ownership history, engine hours, refit records and option packages are all documentable in a way that is not possible with a platform built in the hundreds.
For an owner considering a sale, that same dynamic applies in reverse. There is no inventory surplus to compete against. Correct pricing against verified comparable data and proper presentation in the first 30 days of a listing are the two variables that determine outcome. For current pricing data, verified sold transactions and an analysis of active inventory in this market, see the Ocean Alexander 100 current market guide.
Full specifications and builder documentation for the Ocean Alexander 100 series are available at oceanalexander.com. For context on how the 100 compares to adjacent platforms in the Ocean Alexander model range, including the Ocean Alexander 90R and the larger Revolution and Legend series builds, the models hub covers each platform with the same level of specificity.
Frequently Asked Questions
What are the specifications of the Ocean Alexander 100?
The 2016-to-2020 generation Ocean Alexander 100 measures 100 feet 8 inches LOA with a 23-foot beam and a draft range of 5 feet 6 inches to 6 feet 5 inches. Displacement is 220,264 pounds. Fuel capacity is 4,000 gallons. Power comes from twin MTU 12V 2000 engines producing 1,920 horsepower each, paired with twin Kohler 55 kW generators. Cruising speed is 18 to 19 knots with a maximum of 22 to 24 knots. The platform accommodates 5 staterooms in the standard layout with an on-deck master suite and 3 crew cabins. Total hulls built across the production run was 18.
What is the difference between the Ocean Alexander 100 Skylounge and 100 Flybridge?
The difference is the upper deck configuration. The Skylounge adds an enclosed second salon above the main deck with panoramic windows on all four sides, a helm station, wet bar and electric sliding glass doors to the upper aft deck. The Flybridge places the helm and upper entertainment area in a more open format, with some examples including a flybridge Jacuzzi. Both variants share the same hull, beam, engine package and lower deck accommodation plan. Buyers who cruise frequently in variable weather or use the yacht for extended offshore passages tend to prefer the Skylounge configuration.
How many staterooms does the Ocean Alexander 100 have?
The standard 5-stateroom layout includes an on-deck master suite with a king berth, walk-in closet and private ensuite, two queen guest staterooms on the lower deck and two twin guest staterooms forward that convert to a queen configuration. All staterooms carry private ensuites. A 4-stateroom layout exists on some earlier examples including the 2016 and 2017 builds currently in the market. The 5-stateroom layout is the configuration most buyers in this price range are seeking.
What engines does the Ocean Alexander 100 use?
The 2016-and-later generation carries twin MTU 12V 2000 engines producing 1,920 horsepower each. The 2016 example currently in the market, Sea N Sea, is an exception and carries Caterpillar C32 ACERT engines also rated at approximately 1,925 horsepower each. The 2008 generation used twin MTU 10V 2000 engines at 1,502 horsepower each. MTU extended warranty coverage, where still active, is a meaningful value factor on late-model examples and should be confirmed before any offer is written.
How does the Ocean Alexander 100 compare to the Ocean Alexander 90R?
The 100 adds approximately 10 feet of length, a full foot of additional beam and roughly 30,000 pounds of displacement over the 90R. The on-deck master suite, which is not a feature of the 90R layout, is a defining characteristic of the 100. The Skylounge configuration adds an enclosed upper salon that has no direct equivalent in the 90R. Engine power increases from the 90R's twin MAN or MTU configurations to the MTU 12V 2000 at 1,920 horsepower on the 100. The price gap between the two platforms in the current used market is approximately $1,500,000 to $2,500,000 depending on year and condition.
The Ocean Alexander 100 is a platform that rewards the buyer or seller who approaches it with verified data rather than general market assumptions. Eighteen hulls were built. Each one is known. If you are evaluating a specific example or considering a sale, a private conversation about where that boat sits in the current market is the right starting point.
Owners considering their options can also request a private valuation before committing to a list price or engaging a generalist broker.
Ocean Alexander Specialist
Southeast Florida
561-460-6956