Designed as an accessible and capable daysailer, the San Juan 21 earned a loyal following among sailors looking for an affordable entry point into keelboat sailing without sacrificing genuine performance on the water. Built by Clark Boat Company in the Pacific Northwest, the design became popular across North American lakes and protected coastal waters throughout the 1970s and 1980s, offering a stable and responsive platform for beginner and intermediate sailors alike. The San Juan 21 is well suited to daysailing and casual racing on inland lakes and sheltered bays, where its lively sailing characteristics can be fully appreciated. The boat's manageable size makes it easy to trailer, launch, and maintain, which contributed significantly to its widespread appeal among weekend sailors. Its fin keel configuration provides solid stability and a reasonably predictable feel at the helm, making it forgiving enough for those still developing their skills while remaining engaging for more experienced crews. For buyers researching the used market, the San Juan 21 represents a practical and enjoyable choice for recreational sailing, with an established class community and a reputation for durability and fun.
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- Based on asking prices — not actual sale prices, which are typically lower.
- Condition, year, location, and included equipment are not factored in.
- Outliers are automatically excluded using statistical filtering.
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What is the San Juan 21's sail area to displacement ratio?
The San Juan 21 has a Sail Area to Displacement ratio (SA/D) of 26.25. Values between 14–18 are typical cruising sailboats; 18–22 is cruiser/racer; over 22 is performance racing.
What is the San Juan 21's comfort ratio?
The San Juan 21 has a Ted Brewer Comfort Ratio of 8.01. A ratio over 30 indicates good offshore comfort; over 40 is very comfortable offshore.
Is the San Juan 21 safe for offshore sailing?
The San Juan 21 has a Capsize Screening Formula value of 2.6. Values under 2.0 are considered acceptable for offshore sailing; under 1.8 is ideal.
What is the hull speed of the San Juan 21?
The theoretical hull speed of the San Juan 21 is 5.52 knots, calculated from its waterline length.
How much does a San Juan 21 weigh?
The San Juan 21 has a displacement of 1,250.00 lb and a length overall (LOA) of 20.50 ft.
How much does a used San Juan 21 cost?
Based on 5 recent market listings, used San Juan 21 sailboats typically sell for between $1,000 and $2,500, with a median asking price of $1,000. Price varies significantly based on year, condition, location, and included equipment.
Who designed the San Juan 21?
The San Juan 21 was designed by Don Clark, first built in 1970.