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Australian Kids Life Jacket Size Calculator
Find the right PFD (personal flotation device) size and buoyancy level for your child based on their weight, using Australian AS 4758 standards.
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Always supervise children near water. A correctly fitted PFD is essential but does not replace active adult supervision. Check the PFD tag for weight and buoyancy rating before purchasing. Replace any PFD that is damaged, faded, or no longer fits.
kg
Recommended PFD size
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Weight:
AS 4758 Level:
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PFD Size Chart
Size name
Weight range
Approx age
Recommended PFD level
Infant
Less than 10 kg
Under ~12 months
Level 100 or 150 (infant-specific)
Child Small
10–25 kg
~1–8 years
Level 50 or Level 100
Child Large
25–40 kg
~8–12 years
Level 50 or Level 100
Adult (Junior)
Over 40 kg
~12+ years
Level 50, 100 or 150
AS 4758 Buoyancy Levels
Level
Buoyancy
Best use
Suitable for children?
Level 150
150 N
Offshore / rough water — turns unconscious wearer face-up
Infant-specific styles only
Level 100
100 N
Inshore / general boating — may turn unconscious wearer face-up
Yes — recommended for children
Level 50
50 N
Calm water / jetties / kayaking near shore
Yes — for supervised, calm water use
Level 50S
50 N
Water sports (skiing, boarding) only
Yes — restricted to water sports use
Based on Australian Standard AS 4758. All PFDs sold in Australia must comply with this standard and carry an approved label. Weight ranges shown are typical sizing guides — always check the specific PFD tag for its rated weight range.
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PFD Fit Guide
📏
Check weight rating
The PFD tag shows the weight range it is rated for. Your child's weight must fall within that range — never use an undersized PFD.
🤙
The lift test
With the PFD buckled, grasp the shoulders and lift. Your child's chin and ears should not pass through. If it rides up, it's too big.
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All buckles fastened
Buckle every strap every time. A loose PFD provides significantly less protection and can slip off in the water.
🔍
Inspect before use
Check for tears, faded fabric, broken buckles, or waterlogged foam. A damaged PFD should be replaced — sun and saltwater degrade materials over time.
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Try it in the water
Before any boating trip, practise in a supervised pool with the PFD on. This builds confidence and lets you check that it keeps the child's head above water.
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Replace when outgrown
Children grow fast. Check the fit at the start of every boating season. A PFD that was correct last year may now be too small.
Australian life jacket (PFD) sizing is based on the wearer's weight, regulated under Australian Standard AS 4758. Child PFDs come in infant (under 10 kg), child small (10–25 kg), and child large (25–40 kg) sizes before transitioning to adult sizes. Level 100 is the most commonly recommended level for children in general boating and watersports activities as it provides adequate buoyancy and the best chance of turning an unconscious child face-up. Level 50 is suitable for calm, supervised water close to shore. All PFDs sold in Australia must carry an AS 4758 compliance label. Last updated May 2026.
Level 100 provides more buoyancy (100 Newtons) and is designed to turn an unconscious wearer face-up in calm water — important for children who may be unable to right themselves. Level 50 (50 Newtons) keeps a conscious wearer afloat in calm water but may not turn an unconscious wearer face-up. Level 100 is the recommended minimum for children in boats or near open water.
Yes, in most Australian states and territories children under 12 (and sometimes older) must wear an approved PFD when on a vessel underway. Specific rules vary by state — check with your state's marine safety authority. In all states, PFDs must be worn if you are operating in open water, crossing a bar, or conditions deteriorate.
No. Inflatable PFDs are not approved for use by children under 16 in Australia. Children must use a foam-filled PFD rated for their weight. Inflatable PFDs require the wearer to activate them, which a child in the water may not be able to do reliably.
At exactly 25 kg you are at the boundary of Child Small (10–25 kg) and Child Large (25–40 kg). Try both sizes in-store using the lift test. At boundary weights, the larger size usually provides a better fit with less chance of riding up, and will last longer as your child grows. Always confirm against the specific PFD's weight tag.
Replace a child's PFD whenever it no longer fits, shows signs of deterioration (torn material, faded colour, broken buckles, waterlogged foam), or no longer passes the lift test. There is no fixed replacement schedule — inspect before every use. Most quality PFDs last several seasons with proper care (rinsed with fresh water, stored out of direct sunlight).