A SUP listing says something like 10'8" x 33" plus a volume in litres. Here is what each number means — enough to choose a board without a salesperson.
Why feet and inches
The industry came from surfing, and surfing from English-speaking countries. Hence:
10'8" is 10 feet 8 inches, or 325 cm.
33" is width in inches, or 84 cm.
Quick conversion: a foot is 30.5 cm, an inch 2.54 cm. For estimating, multiply feet by 30 and add inches times 2.5.
Length: speed versus manoeuvrability
A long board goes faster and holds a course. It wanders less, so over distance you spend less effort correcting.
A short board turns on the spot. You want that in waves and tight water.
Guidelines:
- 9' to 10' — waves, turning, children.
- 10' to 11'6" — all-round, the most common choice.
- 12'6" to 14' — touring and racing.
Starboard's range shows it directly: the iGO at 10'8" to 12'0" is the all-rounder, Touring at 12'6" to 14'0" covers distance, All Star at 14'0" races.
Width: the number that matters most for a beginner
Width decides stability, and stability decides whether you enjoy your first session.
Guidelines:
- 32" and up — stable, comfortable for a beginner.
- 30" to 32" — balanced.
- 28" and below — racing, requires skill.
Look at the racing All Star: 14'0" x 24.5" — nearly four and a half metres long at 62 cm wide. A board for someone already standing confidently.
The beginner's classic mistake is buying narrow "to go faster". You will not go faster; you will fall.
Volume: how many litres you need
Litres mean buoyancy. The formula is simple and it works:
Beginner: weight in kilograms × 2. At 80 kg, 160 litres and up.
Confident: weight × 1.5. At 80 kg, around 120 litres.
Advanced in waves: weight × 1 or less.
Count your weight with kit: wetsuit, vest, water, a bag for touring add 5 to 10 kg, and they matter.
Thickness: the number that is not in the label
A fourth parameter, rarely stated in the name, that changes everything.
Inflatables are typically 15 cm. Hence their stability.
Hard boards are 10 to 12 cm. Hence better glide and less stability at equal width.
The practical upshot: comparing an inflatable and a hard board of the same width, remember the inflatable will feel steadier. More on this in our construction comparison.
What the words after the size mean
Starboard's variants carry terms like Deluxe, Deluxe Lite, ASAP, Lite Tech, Blue Carbon, Rhino, Starlite.
Those are constructions, not sizes. The same logic as kite suffixes covered in our suffix guide: the dearer the construction, the lighter and stiffer the board.
In practice: while learning, the difference between constructions will not show. It matters once board weight is your limit — over distance and while carrying.
Matching a size in under a minute
Beginner 70 to 85 kg, calm water → 10'6" to 11'2" × 32"+, 160 litres and up.
Beginner over 90 kg → 11'2" to 12'0" × 33"+, 190 litres and up.
Cruising and distance → 12'6" to 14'0" × 30".
Waves → 9' to 10' × 30" to 32", hard construction.
Two people, or an adult with a child → a tandem or a board from 12'0" with high volume.
A child → a kids' model rather than a smaller adult one: stiffness and weight differ.
Common questions
What does 10'8" x 33" mean?
A length of 10 feet 8 inches (325 cm) and a width of 33 inches (84 cm). A foot is 30.5 cm, an inch 2.54 cm.
How many litres at 80 kg?
A beginner wants 160 litres and up (weight × 2); a confident paddler around 120 (weight × 1.5). Count your kit.
Which parameter matters most for a beginner?
Width. From 32 inches a board is stable; a narrow racer simply will not let you stand.
Why does an inflatable feel steadier at the same width?
It is thicker: around 15 cm against 10 to 12 for a hard board, so more buoyant.
What are Deluxe, ASAP and Blue Carbon?
Constructions rather than sizes: dearer means lighter and stiffer. While learning the difference will not show.
What to read next
Inflatable SUP versus hard and our Starboard review. Boards are in the inflatable and hard SUP sections.
Try before you buy
Rent at the K1 station in Mui Ne and ride the model before buying. Our instructors match the size to your weight and wind.
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