Maxi-Cosi Kani 4-in-1
The Maxi-Cosi Kani 4-in-1 rear-faces up to 40 lb, forward-faces up to 65 lb, and has an expiration of 10 years, per Maxi-Cosi.
- $379.99List price
- 40 lbRear-facing to
- 65 lbHarness to
- 100 lbBooster to
Kani 4-in-1: key facts
- The Maxi-Cosi Kani 4-in-1 rear-faces from 5 to 40 lb and 19 to 40 in tall; forward-faces with a harness from 30 to 65 lb and 34.4 to 49 in tall; works as a booster from 40 to 100 lb and 43.4 to 57 in tall, per Maxi-Cosi.
- Outgrown by height: "Rear-facing: the top of your child's head MUST be at least 1 in. (2.5 cm) below the top of the car seat's headrest. Forward-facing: the top of your child's ears MUST be below the top of the car seat's headrest. Booster: the top of your child's ears should never be above the top of the booster seat's headrest. Backless: the top of your child's ears should never be above the top of the vehicle seat back or vehicle headrest."
- It installs with 1-click LATCH connectors.
- Maxi-Cosi says it expires 10 years after the date of manufacture.
- Maxi-Cosi lists it as certified for aircraft ("This restraint is certified for aircraft use when used with the internal harness. / Booster Seat: This restraint is not certified for aircraft use, when used as a booster seat, because aircraft seats do not have shoulder belts.").
From Maxi-Cosi's manual and published specs. Always follow the limits on your seat's labels.
How the Kani 4-in-1 stacks up
Against the 57 all-in-one car seats we track. The shaded band is where the middle half of them fall; the dot is this one.
The same as most all-in-one car seats (10 years).
The same as most all-in-one car seats (40 lb).
Within the typical range for all-in-one car seats ($229.99 to $399.99).
What sets the Kani 4-in-1 apart
Measured against the 57 all-in-one car seats we compare, from each maker's published specs.
Next to its closest matches
- Joie matcha spin SINext to it, the Kani 4-in-1 is $20 less; no rotates (the matcha spin SI has it); has aircraft label (the matcha spin SI doesn't).
Flying with the Kani 4-in-1
Maxi-Cosi's label: “This restraint is certified for aircraft use when used with the internal harness. / Booster Seat: This restraint is not certified for aircraft use, when used as a booster seat, because aircraft seats do not have shoulder belts.”
What airlines say about car seats:
- American: “Each ticketed customer is allowed 1 stroller and 1 car seat to be checked free of charge” “If an unoccupied, adjoining seat is not available, the gate agent will check the safety seat to your final destination.” Source
- Alaska: “We will transport your child's car seat and stroller free of charge as checked baggage.” Source
- JetBlue: “Checking a child safety seat will not count towards your checked baggage allowance and there is no fee assessed” Source
- Spirit: “One (1) car seat will be accepted per child as checked baggage at no charge.” Source
- Frontier: “strollers and car seats can be checked for free.” Source
- Allegiant: “There is no charge for checking or gate checking one car seat per fare-paying passenger.” Source
- Breeze: “Child seats may be carried on board the aircraft if a seat has been purchased for the Infant or Child” Source
Quoted from each airline's page as of 2026-11-02.
Listed features
- Maker lists 1-click LATCH connectors
- Maker lists 10-position QuikFit headrest and harness and 5 recline positions
- Maker states 'Aircraft Use: Yes'
- Maker states the fabric is 'made without added fire retardant treatment'
Where to buy the Kani 4-in-1
Prices and availability change. We may earn a commission from some links.
- Check for recalls: Search the agency's recall list with the model number and date code from the label: NHTSA recall search.
- Car seat use and installation: see NHTSA's car seat page, which also lists free car seat inspection by certified technicians. Check the label and the maker's instructions, and ask your pediatrician about your child.
Full specs
| Maxi-Cosi Kani 4-in-1 | |
|---|---|
| Type | All-in-one |
| List price | $379.99 |
| Rear-facing weight | 5–40 lb |
| Rear-facing height | 19–40 in |
| Forward-facing weight | 30–65 lb |
| Forward-facing height | 34.4–49 in |
| Booster weight | 40–100 lb |
| Booster height | 43.4–57 in |
| Head rule | Rear-facing: the top of your child's head MUST be at least 1 in. (2.5 cm) below the top of the car seat's headrest. Forward-facing: the top of your child's ears MUST be below the top of the car seat's headrest. Booster: the top of your child's ears should never be above the top of the booster seat's headrest. Backless: the top of your child's ears should never be above the top of the vehicle seat back or vehicle headrest. |
| Newborn insert | Head pillow and body pillow, optional, rear-facing mode only; must be used together (manual). |
| Installation | 1-click LATCH connectors |
| Load leg | No |
| Anti-rebound bar | No |
| Rotates | No |
| Harness heights | 10 |
| Recline positions | 5 |
| Aircraft label | Certified for aircraft, per the maker |
| No added flame retardants | Yes |
| Expires after | 10 years |
Compare the Kani 4-in-1 with
How each closest rival differs from the Kani 4-in-1, from the makers' specs.
- ChiccoOneFit Max ClearTexrear-facing to 40 lbforward-facing to 65 lb$379.99Compare side by side
- Graco4Ever DLX Slim 4-in-1rear-facing to 40 lbforward-facing to 65 lb$369.99
- $10 less
- Joiematcha spin SIrear-facing to 40 lbforward-facing to 65 lb$399.99
- $20 more
- GracoTurn2Me 3-in-1rear-facing to 40 lbforward-facing to 65 lb$399.99
- $20 more
Kani 4-in-1: questions answered
From Maxi-Cosi's published specs, last checked 2026-11-06.
Does the Maxi-Cosi Kani 4-in-1 rear-face longer than other all-in-one seats?
15 of the 70 all-in-one seats we track rear-face to a higher weight than its 40 lb. The highest is the Britax One4Life ClickTight All-in-One at 50 lb. NHTSA: stay rear-facing "until he or she reaches the top height or weight limit allowed by your car seat's manufacturer." (NHTSA)
Can you bring the Maxi-Cosi Kani 4-in-1 on a plane?
Yes, Maxi-Cosi lists it as certified for aircraft; look for the red-lettered label that says so. The FAA asks that a car seat go in a window seat so it doesn't block the aisle, and the crew will look for that label.
Is it OK to buy a used Kani 4-in-1?
NHTSA publishes guidance on used car seats on its car seat page. Maxi-Cosi lists a lifespan of 10 years from manufacture for this model. Check the label and the maker's instructions, and ask your pediatrician about your child.
Still wondering? Write to us at hello@cribpicks.com and we'll look it up.
More all-in-one car seats
- Disney BabyTurn and Go 360 Rotating All-in-Onerear-facing to 40 lbforward-facing to 65 lb$399.99
- EvenfloRevolve360 Rotating All-In-Onerear-facing to 40 lbforward-facing to 65 lb$349.99
- Safety 1stTurn and Go 360 Rotatingrear-facing to 40 lbforward-facing to 65 lb$349.99
- Safety 1stTurn and Go 360 DLXrear-facing to 40 lbforward-facing to 65 lb$349.99
- Graco4Ever DLX Grad 5-in-1rear-facing to 40 lbforward-facing to 65 lb$429.99
- Maxi-CosiPria Maxrear-facing to 40 lbforward-facing to 65 lb$329.99
Where these specs come from
- maxicosi.com/products/kani-4-in-1-convertible-car-seat-cc430
- images.salsify.com/image/upload/s--HbBlI0sd--/xkduoebszl7348k18pj5
Last checked 2026-11-06. Spot something wrong? Tell us. Read our editorial and safety policy and corrections.