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UPPAbaby Knox

The UPPAbaby Knox rear-faces up to 45 lb, forward-faces up to 65 lb, and has an expiration of 10 years.

DiscontinuedNo longer made or sold new. Specs are kept for comparing generations. Replaced by UPPAbaby Rove.

  • 45 lbRear-facing to
  • 65 lbHarness to

When does it expire?

All convertible car seats

Knox: key facts

  • The UPPAbaby Knox rear-faces from 14 to 45 lb and up to 49 in tall; forward-faces with a harness from 25 to 65 lb and up to 49 in tall, per UPPAbaby.
  • Outgrown by height: "DO NOT use this Child Restraint system if the top of the child’s head is less than 1” from the top of the headrest when in its highest position."
  • It installs with seat belt rear-facing (lap/shoulder), lap belt rear-facing, LATCH rear-facing, rear-facing tether (Multi-Directional Tether), seat belt forward-facing + top tether, lap belt forward-facing + top tether or LATCH forward-facing + top tether.
  • UPPAbaby says it expires 10 years after the date of manufacture.
  • UPPAbaby lists it as certified for aircraft ("This Child Restraint is certified for aircraft use. / CERTIFIED FOR AIRCRAFT TRAVEL: THIS CHILD SEAT IS CERTIFIED FOR AIRCRAFT USE.").

From UPPAbaby's manual and published specs. Always follow the limits on your seat's labels.

How the Knox stacks up

Against the 40 convertible car seats we track. The shaded band is where the middle half of them fall; the dot is this one.

Expiration10 years

Within the typical range for convertible car seats (9 years to 10 years).

This one
7 yearsmiddle 10 years10 years
Rear-facing limit45 lb16th highest rear-facing limit of 39

Within the typical range for convertible car seats (40 lb to 50 lb).

This one
35 lbmiddle 40 lb65 lb
Forward-facing limit65 lbHighest forward-facing limit of 39 convertible car seats

The same as most convertible car seats (65 lb).

This one
40 lbmiddle 65 lb65 lb

Knox: generations

From each maker's published specs.

Flying with the Knox

UPPAbaby's label: “This Child Restraint is certified for aircraft use. / CERTIFIED FOR AIRCRAFT TRAVEL: THIS CHILD SEAT IS CERTIFIED FOR AIRCRAFT USE.”

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.

Where to buy the Knox

Prices and availability change. We may earn a commission from some links.

good to know
  • Discontinued. You may still find it used or on clearance.
  • 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

UPPAbaby Knox
TypeConvertible
Rear-facing weight14–45 lb
Rear-facing heightUp to 49 in
Forward-facing weight25–65 lb
Forward-facing heightUp to 49 in
Head ruleDO NOT use this Child Restraint system if the top of the child’s head is less than 1” from the top of the headrest when in its highest position.
Newborn insertFit Inlay, 'designed for children who weigh 14–25 lbs (6.4–11.3 kg)'; 'Remove the Fit Inlay at 25 lbs (11.3 kg) or when the child begins' growing on top of the buckle
Installationseat belt rear-facing (lap/shoulder), lap belt rear-facing, LATCH rear-facing, rear-facing tether (Multi-Directional Tether), seat belt forward-facing + top tether, lap belt forward-facing + top tether, LATCH forward-facing + top tether
Load legNo
Anti-rebound barNo
RotatesNo
Recline positions4
Aircraft labelCertified for aircraft, per the maker
Expires after10 years

Compare the Knox with

How each closest rival differs from the Knox, from the makers' specs.

Ask the meadow

Knox: questions answered

From UPPAbaby's published specs and retailer listings, last checked 2026-11-06.

Does the UPPAbaby Knox rear-face longer than other convertible seats?

17 of the 50 convertible seats we track rear-face to a higher weight than its 45 lb. The highest is the Axkid One 3 at 65 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 UPPAbaby Knox on a plane?

Yes, UPPAbaby 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.

Knox or chili spin 360: what's different?

By the makers' specs, the chili spin 360 has a rotating seat. See every spec side by side.

Is it OK to buy a used Knox?

NHTSA publishes guidance on used car seats on its car seat page. UPPAbaby 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 convertible car seats

  • ChiccoNextFit Max ClearTexrear-facing to 50 lbforward-facing to 65 lb
  • CybexSirona Mrear-facing to 40 lbforward-facing to 65 lb
  • BabyarkSmartrear-facing to 50 lbforward-facing to 65 lb$990
  • Orbit BabyG5 Toddlerrear-facing to 35 lbforward-facing to 65 lb
  • NunaREVVrear-facing to 30 lbforward-facing to 40 lb
  • NunaREVV maxxrear-facing to 40 lbforward-facing to 65 lb$800

Where these specs come from

Last checked 2026-11-06. Spot something wrong? Tell us. Read our editorial and safety policy and corrections.