J/121
Specifications
Hull
| LOA | 40 ft |
| LWL | 35.78 ft |
| Beam | 12.3 ft |
| Draft | 7.75 ft |
| Displacement | 11,900 lb |
| Ballast | 4,800.5 lb |
| Hull speed1.34·√LWL | 8.0 kn |
About the J/121
The J/121 includes a water ballast system with a 104 gal (394 liter) tank on each side. This system allows up to an additional 867 lbs (approx) to the rail. Some specs and photo are from a review by Adam Cort in Sail Mag. Feb 8, 2018.
The J/121 is a performance-oriented 40-foot fractional sloop designed by Alan Johnstone and built by J Boats, with production records indicating a start year of 2018. As a modern entry in the J/Boats lineup, it combines a lightweight displacement of 11900.0 lb with a high sail area-to-displacement ratio of 29.54, targeting owners who prioritize speed and responsive handling.
- Best for:
- This boat is best suited for active coastal cruisers and weekend racers who value performance and ease of handling, particularly those interested in the fractional rig configuration. It appeals to sailors who want a modern, fast hull form without the complexity of a heavy bluewater cruiser.
- Bluewater capability:
- With a capsize ratio of 2.16 and a comfort ratio of 17.55, the J/121 is designed primarily for coastal and inshore racing rather than heavy offshore passage-making, though its fin keel and fractional rig provide adequate stability for protected waters.
- Comparables:
- Comparable boats include the J/122 and J/125, which share the same designer, builder, and performance-focused fractional rig philosophy. It also competes with the Beneteau First 40.7 and the Nauticat 42, offering similar length overall (40.0 ft) but with a significantly lighter displacement and higher sail area ratio.
Performance
Estimated Value
Limited DataEstimated Cost of Ownership
Based on 40ft LOA. Actual costs vary by condition, usage, and local rates.
Known Issues & Pre-Purchase Inspection
We don't have enough data on the J/121yet to publish model-specific findings we'd stand behind — but here's a free general inspection checklist, built from our research into what actually goes wrong on boats of this kind.
Drawn from 7,029 documented issues across 2,391 models, ordered so the areas that most often turn up problems come first.
Own a J/121? Reports from owners are what turn this into a model-specific checklist — and they're the reason the boats above it have one.
Similar Sailboats
Which engine powers your J/121?
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Used sails that fit the J/121
Checking eBay for sails sized to this boat's rig…