In Depth Baby Product Reviews Led by a Pediatrician

UPPAbaby Knox Review

Nice quality and comfort, but the bulk and below-average crash test analysis left us wanting
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UPPAbaby Knox Review
Credit: Abriah Wofford
Price:  $300 List
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Manufacturer:   UPPAbaby
By Juliet Spurrier, MD & Wendy Schmitz  ⋅  Jan 5, 2024
65
OVERALL
SCORE


RANKED
#12 of 19
  • Crash Test - 35% 6.9
  • Ease of Installation - LATCH - 20% 6.0
  • Ease of Installation - Belt - 15% 5.5
  • Ease of Use - 15% 6.0
  • Comfort/Quality - 10% 8.5
  • Weight/ Size - 5% 6.7

Our Verdict

The UPPAbaby Knox did not perform as well as other UPPAbaby products have in different categories, and we are bummed to say it is not one of our favorite convertible car seats. The only place the Knox excelled was the comfort and quality metric. This is not surprising, given that we are usually impressed with the quality of UPPAbaby options. It has nice padding, softer fabric, and a cozy seating area. However, it is hard to install and harder to use. Even if you are willing to put up with these quirks, the crash test analysis results were the nail in the coffin for this convertible seat. While it didn't earn the lowest result, and it did pass the federal guidelines and is considered safe, it couldn't keep up with the competition in our hotter tests. Overall, the Knox is not a seat we recommend.
REASONS TO BUY
Excellent comfort and quality
Sturdy installation
REASONS TO AVOID
Heavy and bulky
Shorter shoulder straps
Longer installation times
Editor's Note: On January 5, 2024, we updated our convertible car seat review to include the Knox and 20 other seats we had independently crash-tested for comparison.

Compare to Similar Products

 
uppababy knox
This Product
UPPAbaby Knox
Awards  Editors' Choice Award
Best Overall Convertible and Crash Testing
Editors' Choice Award
Best Overall for Rear-Facing Longer
Best Value Award
Best Value Convertible Seat
Best Value Award
Best on the Tightest Budget
Price $300 List
$299.99 at Amazon
$330 List
$329.99 at Amazon
$250 List
$229.99 at Amazon
$220 List
Check Price at Amazon
$80 List
$79.99 at Amazon
Overall Score Sort Icon
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Star Rating
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Bottom Line Comfy seat with better quality, but the lower crash test analysis results and overall size resulted in an overall lower scoreEasy to install and use and one of the best crash test analysis scores make this seat a winner for most familiesBetter crash test analysis and a lower price make this easy-to-install seat an award contender that just missed the markWallet-loving price on a seat that is easy to install and earned better crash test results than mostDespite a lack of padding and a harder LATCH install, this inexpensive option earned impressive crash test results, making it a winner for budget-limited families
Rating Categories UPPAbaby Knox Graco 4Ever DLX Graco Extend2Fit 3... Graco SlimFit 3-in-1 Evenflo Tribute 5
Crash Test (35%)
6.9
8.8
8.6
8.5
8.6
Ease of Installation - LATCH (20%)
6.0
7.9
7.8
7.9
4.3
Ease of Installation - Belt (15%)
5.5
7.1
6.4
6.5
5.6
Ease of Use (15%)
6.0
8.0
7.0
7.5
5.0
Comfort/Quality (10%)
8.5
6.5
8.5
8.0
3.0
Weight/ Size (5%)
6.7
7.5
7.5
7.1
7.8
Specs UPPAbaby Knox Graco 4Ever DLX Graco Extend2Fit 3... Graco SlimFit 3-in-1 Evenflo Tribute 5
Min/Max Rear Facing Passenger Weight 14-45 lb 4-40 lb 4-50 lb 5-40 lb 5-40 lb
Min/Max Forward Facing Passenger Weight 25-65 lb 22-65 lb 22-65 lb 22-65 lb 22-40 lb
Rear Facing Maximum Height 49 in Top of head must be at least 1 in below handle Top of head must be at least 1 in below handle Top of head must be at least 1 in below handle 37 in
Forward Facing Maximum Height 49 in 49 in 49 in 49 in 40 in
Weight 31.4 lb 21.8 lb 20.5 lb 18.5 lb 9.4 lb
Minimum Rear Facing Length 28 in 25 in 26 in 28 in 29 in
Minimum Seat Width 19 in 19 in 19 in 19 in 18 in
Number Of Recline positions 4 6 6 4 1
Shoulder Harness Positions 8 10 10 10 4
Crotch Strap Positions 1 2 2 3 2
Anti-rebound Device No No Yes No No
Head Support Yes Yes Yes Yes Yes
Infant Positioning Insert Yes Yes Yes Yes No
Harness Type No-rethread No-rethread No-rethread No-rethread Rethread
Onboard Manual Storage Yes Yes Yes Yes Yes
Rear Facing Level Indicator On Seat Bead in water, both sides Bubble, one side Bubble, one side Bead, one side Line on decal, both sides
Booster Mode Available No Yes Yes Yes No
Foam Type EPP Not mentioned Not mentioned EPS EPS
Seat Lifespan 10 years 10 years 10 years 10 years 6 years
Aircraft Certified Yes Yes in harness mode, No in booster mode Yes in harness mode, No in booster mode Yes in harness mode, No in booster mode Yes
Warranty Lifetime limited 1 year limited 1 year limited 1 year limited 90 day limited

Our Analysis and Test Results

Family-owned UPPAbaby specializes in creating a variety of baby gear with a concentration on strollers and car seats. This American company pulls inspiration from family and has over a decade of experience creating baby-friendly products.

Performance Comparison


The Knox was not a top performer in our commissioned crash test with MGA Research.
Credit: GearLab & MGA Research

Crash Test


This car seat earned a below-average crash test analysis score compared to the crash test sensor results from the competition. It isn't the lowest-scoring option, but it is still not impressive compared to higher-scoring seats.


While all seats in our review have passed federal safety guidelines and are considered safe, we hoped to identify those seats that stand out from the competition. To do this, we ran a faster test on a crash sled that aligns closer to the modern vehicle than that used in the federal testing.

The Knox chest clip sensor results are shown here in black compared...
The Knox chest clip sensor results are shown here in black compared to those of one of the higher-performing options in green.
The Knox HIC (head) sensor results are shown here in black compared...
The Knox HIC (head) sensor results are shown here in black compared to those of one of the Graco 4Ever (in green), which was one of the higher-performing options.

We assumed we'd see a wider range of sensor data than we might using the federal standard. The Knox HIC and chest sensors recorded more G-forces than the average seat. Fewer G-forces are better, and the combined higher results for the Knox hurt its overall analysis score. While it wasn't the lowest performer, it was in the lower third of the convertible seats we tested.

Because you slide the Knox LATCH strap in a slot, you need to be careful not to twist the strap.
Credit: Abriah Wofford

Ease of Install - LATCH


With a LATCH installation score below the average, the Knox is neither easy nor super challenging to install using this method. The Knox has no lock-off, typically leading to more issues during installation than those with lock-offs or tensioners. There is a bead-in-liquid level indicator on both sides, and the LATCH connectors are push-style on a flexible strap.

Even when the Knox indicator showed green that the strap was tight enough, we were able to wobble the seat quite a bit.
Credit: Abriah Wofford

The Knox has a lot of steps for LATCH installation, especially when you consider it is supposed to be the easier and more foolproof installation process. The LATCH strap pathway isn't apparent, and even the manual didn't clarify it.

The Knox recline adjustment is nicely placed compared to most...
The Knox recline adjustment is nicely placed compared to most competitors, with a location you can more readily access.
The Knox has a push-style connector with a button release.
The Knox has a push-style connector with a button release.

The recline handle is on the back, which we like, and it is easy to adjust but doesn't go back very far. UPPAbaby does offer a setup video, which can help make things easier and answer common questions about installation.

The Knox manual is not clear on how to use the lock-offs, and the...
The Knox manual is not clear on how to use the lock-offs, and the manufacturer video seemed to contradict the written instructions.
The Knox seat cover has handy zippers for easier access to the...
The Knox seat cover has handy zippers for easier access to the pathway and lock-off locations.

A lot is going on with this seat, including unzipping fabric for the access you need and a relatively unique tether strap for the rear-facing configuration. We also had trouble getting the main LATCH strap tight enough and had to put a knee in the seat for leverage. The Knox is a big seat, and it was cumbersome to manipulate in tight back seats.

uppababy knox - the knox has a color-changing indicator from red to green to help...
The Knox has a color-changing indicator from red to green to help parents know when the strap is tight enough.
Credit: Abriah Wofford

There is a color change indicator to let you know it is tight enough. It seems like a reassuring idea for nervous parents, but we struggled to get a complete switch to green. We were exhausted getting it to part green. It did feel pretty solid once installed.

The Knox is one of the only options we've ever seen with a top...
The Knox is one of the only options we've ever seen with a top tether in the rear-facing configuration.
The top tether on the Knox is a required component of the...
The top tether on the Knox is a required component of the installation.

The Knox is a big seat and more challenging to move around than many competitors. The pathway has insets, making moving the strap through more of a challenge, and you'll need the manual to confirm the path (always use the manual!). Pushing the car seat into the vehicle seat to tighten the strap takes a lot of effort and feels like a workout. Once installed, it feels secure, probably due to its size and tightening. Nothing for the Knox is overly hard, but a lot is going on, and it felt more convoluted than some of the easier-to-install seats we tested.

The Knox recline adjustment is on the back and is easy to use in rear-facing installation, and the ball in a groove level indicator is clear and easy to read.
Credit: Abriah Wofford

Ease of Install - Belt


The Knox continues to be challenging to install with the vehicle belt, with a score that is once again below average for the group but isn't as frustrating as those that lack features like a lock-off.

uppababy knox - whether you use the knox latch strap or the vehicle belt, both...
Whether you use the Knox LATCH strap or the vehicle belt, both require a top tether attachment.
Credit: Abriah Wofford

The rear-facing installation of the Knox includes a bead-in-water level indicator, a color-coded pathway, and a lock-off. The recline adjustment handle is on the back of the seat, which makes it easier to use and adjust without shifting the whole seat back and forth to check it. The color-coded pathway is a bonus, but the division of the shoulder and lap portions of the belt took some consideration.

The Knox has lock-offs on the belt path, but how and which to use is...
The Knox has lock-offs on the belt path, but how and which to use is not clear in the provided information or manufacturer video.
The Knox belt pathway is color-coded to make threading more...
The Knox belt pathway is color-coded to make threading more straightforward.

The pathway has lock-off clips along with a directional pull slit underneath for the lap belt. The belt was easy to pull and get it where it needed to go without twisting, and there is a color indicator to reassure you it is tight enough. The wide, solid base and useful lock-off make it one of the more stable options we tested.

You need to unzip and flip back the seat padding/cover on the Knox...
You need to unzip and flip back the seat padding/cover on the Knox to expose the pathway.
Once the Knox fabric is pulled back, threading the belt is...
Once the Knox fabric is pulled back, threading the belt is straightforward.

The Knox forward-facing installation has color coding and a slit-style lock-off. The indicator is confusing, and there isn't enough guidance to know how to use it for forward-facing. The lock-off is hard to work with and requires lots of shimmying of the strap to get things in place. If it isn't tight enough, you have to take it out, tighten it, keep it taunt, and then shimmy it back in place. Whew! It felt pretty stable, but the tightening hurt its overall score compared to top contenders.

The Knox LATCH connectors are stored in a compartment on the foot of the chair portion of the seat.
Credit: Abriah Wofford

Ease of Use


The Knox isn't that easy to use, but it isn't the hardest, and we suspect that while not a standout, parents who haven't tried anything else won't be overly frustrated.

uppababy knox - the knox has retention slots for the harness prongs on either side...
The Knox has retention slots for the harness prongs on either side of the cover.
Credit: Abriah Wofford

Harness


This harness needs more webbing on the shoulder straps. They are relatively short, and it makes getting them around arms more of a challenge than it is with other seats. The crotch buckle comes up high, and it has a big button that is easy to press, and the prongs sort of pop out to help. The buckle button is easy to press, and the chest clip works smoothly.

The tightening strap has a curious loop on the end that isn't big enough for even petite fingers. It's not a big deal; you don't need it, but it seems strange. The strap is easy to pull, but it is shorter than most, and you can tell when using it that there is less webbing for fitting than the harness than most competitors. The button has sort of a double button with a plastic part over the lever that releases the strap. We had to push it back to get the strap to release. The Knox system is average compared to most of these tests.

uppababy knox - the knox buckle and chest clip are easy to operate, but we wish...
The Knox buckle and chest clip are easy to operate, but we wish there were more strap length for bigger babies.
Credit: Abriah Wofford

Shoulder strap height adjustment is a non-rethread style adjustment with eight potential height options and one crotch strap. We worry that some of these seats with only one buckle strap position could make getting a snug fit more challenging. Getting the shoulder straps moving takes more effort than most, but it is relatively smooth once you get it going. It does have some resistance due to the padding on the sides.

uppababy knox - the latch storage compartment on the knox is near the foot portion...
The LATCH storage compartment on the Knox is near the foot portion of the chair.
Credit: Abriah Wofford

LATCH Storage


LATCH connector storage is on the front of the seat, and there are a few buttons to operate to gain access, but it is still average for the group.

The Knox user manual is stored in a pocket on the padding-bottom...
The Knox user manual is stored in a pocket on the padding-bottom, which could become soiled if liquids spill on the seat.
There is a visual tag on the cover of the Knox to remind you where...
There is a visual tag on the cover of the Knox to remind you where the user manual is stored.

Cover


The slots on this attachment make it super hard to pull the cover off, and we somewhat damaged the fabric trying to get it off. Removal and replacement are below average for the Knox compared to the others we tested.

uppababy knox - overall, like many uppababy products, we like the quality and...
Overall, like many UPPAbaby products, we like the quality and comfort of the Knox.
Credit: Abriah Wofford

Comfort/Quality


Like other UPPAbaby products, the Knox is an impressive option for comfort and quality. The Knox has very good and better-than-average results in the sub-metrics within this metric.

The main seat and headrest are all the same fabric. It feels skin-friendly when tested on our cheeks. The infant insert also has smooth fabric and lush padding. There is an additional booster block with a foam pad, but nothing extra for the head area beyond the main cushy headrest.

uppababy knox - the plastic shell on the knox is nice looking and offers a...
The plastic shell on the Knox is nice looking and offers a polished-style finish.
Credit: Abriah Wofford

The padding on the seat is somewhat lacking. When you pull up on the impressive headrest, the backside underneath doesn't offer much on the lower back. The sides are oddly super padded when the bottom area is not. This design feels like a misstep, given where you'd want more support.

The plastic shell is higher quality than most, and you can't see any scratches. It has a slight texture and is one of the best-looking in the group. There is one cup holder you can place on either side.

uppababy knox - the knox is a beast of a seat with one of the highest weights in the...
The Knox is a beast of a seat with one of the highest weights in the group.
Credit: Abriah Wofford

Weight/Size


The Knox is heavy at 31.4 lbs. Only a handful of seats are heavier; the lightest is closer to 9 lbs. If you plan to use it on travel or carpooling or need to carry it, we suspect it isn't the right choice for your needs.


It is also only average for width, with the GearLab measured width of 18.6 inches, which is the average for this review. Whether its weight or width will work for you, it is noteworthy that it is very top-heavy and will not stay upright unless it has weight in the seat or is securely installed.

Should You Buy the UPPAbaby Knox?


We love UPPAbaby, but the Knox did not meet our expectations of other products in the UPPAbaby lineup. With below-average performance in almost every test metric, it is hard to recommend this option, even for hardcore UPPAbaby lovers (we see you!). Except for comfort and quality, which is on par with our expectations for this brand, the Knox struggled to meet the average scores of the competition, and we were left feeling uninspired. The lower crash test analysis result and higher price sealed the deal that this is not a seat we think many families will love.

What Other Convertible Car Seat Should You Consider?


The Graco 4Ever DLX is the best all-around seat in this lineup. It has the best crash test analysis results and a comfy seating area with a non-rethread harness and dual cup holders. Parents will find it easy to install, and it has a reasonable price that is average for this group of competitors. If price is an issue, the Graco SlimFit 3-in-1 should also be considered, as it has a very similar metric makeup to the 4Ever but has a lower budget-friendly price. If your goal is the highest-scoring seat and money isn't a factor, the Nuna Rava has impressive performance in crash testing, ease of installation, and more. The only drawback here is the unusually high price and perhaps the bigger size.

Manufacturer Video



Juliet Spurrier, MD & Wendy Schmitz