In Depth Baby Product Reviews Led by a Pediatrician
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The Cybex Aton 2 is one of our favorite car seats and an impressive option. With the best crash test score and some of the best crash test sensor data in our best infant car seat review, this seat is a top contender for anyone with safety on the brain. It looks great and scores above average in most metrics. It is also one of the easiest products to install using LATCH and offers above-average comfort and quality with soft fabric and thicker padding. On the downside, it isn't compatible with many strollers, but you could use a hands-free, top-ranked baby carrier instead. The Aton 2 is a bit more expensive, but it is worth it if it fits your budget.
REASONS TO BUY
Best crash results
Easy LATCH
Additional safety features
Comfy
REASONS TO AVOID
Higher price
Hard to use
The Cybex Aton 2 is no longer available, and it's now the Cybex Aton 2 with SensorSafe. The SensorSafe technology is built into the chest clip and provides instant alerts about your child's safety and well-being. We are now linking to the Sensor-Safe version and hope to test it soon.
Recall Notice for Some Cybex Aton 2 Models
The National Highway Traffic Safety Administration (NHTSA) has recently indicated a found flaw in some Cybex infant car seats prompting a recall. This includes some Aton 2 products due to a potential issue with the webbing strap used in the central front seatbelt adjuster. Check the Cybex website to learn more specifics about the affected models and remedy.
Editor's Note: We made updates to this review on December 20, 2021. These updates include more details concerning the tests we conduct for the highest weight metrics. These details create an easier side-by-side comparison.
Our Analysis and Test Results
Originating in Germany, the Cybex company became part of Goodbaby International Holdings Ltd. In 2014. Cybex is a maker of some of the best car seats, carriers, and top-ranked strollers for babies created with city life in mind. The company focuses on functionality, safety, and design to create innovative gear.
Performance Comparison
The Cybex Aton 2 comes standard with a load leg. We crash tested two Aton 2 seats: one without the load leg deployed and then second crash test with the load leg. We found the Cybex load leg was very effective in significantly improving crash test performance.
Credit: Abriah Wofford
Crash Test
The Cybex crash test results suggest it provides a better level of protection than many competing seats for the forces recorded by the head and chest sensors in the crash dummy.
While all the seats meet the minimum guidelines for crash tests, some seem to offer an additional margin of protection with scores further from the Federally allowed maximum. The Aton 2 was middle of the pack in crash test results without the load leg. However, it performs better when using the load leg and, therefore, logically, should be used with the load leg.
The Aton has the second best HIC results in the group rivaled only by the Chicco Keyfit 30 with a comparison of 340 vs 330.
Credit: BabyGearLab Staff, MGA Research
The Aton 2 has the best chest sensor crash test results with a 44.
Credit: BabyGearLab Staff, MGA Research
The charts above compare the Cybex using the load leg (in black) to the seats with the best crash test results (in green) based on the head (HIC) and chest force (g clip) sensors of the crash test dummy. Below is a chart of the chest sensor results for each seat we tested.
The Cybex has the best chest sensor result (44 g clip) in the group where the maximum allowed is 60, and a lower number is better. Below is the HIC chart showing the results for all of the products tested.
The Aton2 has the second-best HIC results (340 HIC) in the group where the maximum allowed is 1000, and a smaller number is better. Only the Chicco Keyfit 30 has a lower result of 330. Both sensor results are significantly better than the Federal requirements and, thus, could be viewed as providing an extra margin of protection relative to the competition.
The Cybex has a unique side-impact device located on the handle that their marketing claims will reduce or transfer the impact of crash forces to the shell of the seat. While we don't have proof it works as advertised, it is a feature unique to Cybex. You can only use it if no passengers are sitting next to the seat.
This photo shows the Cybex Aton 2 load leg in action
Credit: Abriah Wofford
The load leg helps stabilize the seat's base and can potentially decrease the rotation or rebound the seat will experience in a crash (as claimed by the manufacturer). According to our crash tests with and without the leg, the Aton 2 benefits by using the leg.
Installation of the Aton 2 with the LATCH connectors includes a one-sided tightening strap.
Credit: Abriah Wofford
Ease of Install - LATCH
The Cybex is one of the easiest options to install using the LATCH method.
The Aton 2 is one of only a few seats that come with plastic pockets for easier access to the LATCH anchors on the vehicle.
Credit: Abriah Wofford
The Cybex car seat came with LATCH guides that help make access to the U anchors on the vehicle more visible and easier to reach. These guides are made of plastic and essentially create a pocket for the connectors to go through, so you have better access.
We liked the idea, and it does make the process somewhat easier, but the guides don't stay in place and usually come loose from the vehicle seat, so the result is they float around on the strap. This floating isn't a big deal, and you can still use them, but it is annoying, and it would be more helpful if they stayed in the seat crevice.
The Aton has the easier to use push on connectors for LATCH.
Credit: Abriah Wofford
The Cybex has push-button connectors for LATCH. We think this style is easier to connect and disconnect. They worked nicely with the guides and were easy to use. The straps are also more comfortable to tighten and loosen than the competition. Overall, this seat is easy to install and secure in every car we used.
Installation of the Aton 2 using the vehicle belt and base uses a lock off on the base and is the second easiest method of installation for the Aton.
Credit: Abriah Wofford
Ease of Install - Belt
The Cybex is somewhat harder to install using the vehicle belt.
Its performance is above average and arguably good enough for something you might not need to do.
The vehicle belt lock off on the base of the Aton 2 is designed to help parents achieve a tight strap for installation.
Credit: Abriah Wofford
The Cybex has an interesting belt lock-off system that helps parents achieve a tight and secure installation using the vehicle belt. The lock-off is relatively easy to use, and the color-coded belt path makes the belt path straightforward. The lock-off gets/keeps the belt extremely tight, almost too tight, and occasionally we had trouble closing it. There is no reason to struggle with the vehicle belt to get a tight fit, and parents lacking upper body strength will appreciate the feature that prevents frustration.
The level on the Aton 2 is a ball in groove design that typically functions well and is easy to read.
Credit: Abriah Wofford
This seat has a level on the base for help finding the proper installation angle. The little ball in the level tends to catch on the inside of the casing, and we think it would work better if the ball were metal or the level was the liquid/bubble style. However, it is better than a line on the seat side.
The base of the Aton 2's seat can adjust to help find the right angle for installation.
Credit: Abriah Wofford
The base has an adjustable foot that can be altered to help with installation. It is one of the easiest in the review to use and can be adjusted even after you have tightened the base to the vehicle seat.
INstalling the Aton without the base is somewhat harder than the competition making it potentially a poor choice if you plan to go sans base frequently.
Credit: Abriah Wofford
Ease of Install - Without the Base
The hardest installation method for the Cybex was installing without the base due to a threading issue and a less stable final result than some of the competition. This means it may be a poor choice for those who plan to frequent public transportation.
The European belt path includes using the vehicle's shoulder strap around the back of the carrier to pull it snuggly to the vehicle seat.
Credit: Abriah Wofford
The Cybex has a color-coded European belt path. We prefer this method because it feels more secure with the shoulder strap wrapped around the carrier. Threading the belt was challenging for some testers, and we had to use a towel in our test truck but not in the sedan or SUV. It is also significantly more difficult to unthread the belt when you are ready to uninstall the carrier, as it can require some finagling.
The exaggerated belt threading hooks on the lower portion of the Cybex make it easier to install without the base than some of the competition
Credit: Abriah Wofford
This seat can install using the American method by threading the belt across the lower portion of the carrier, which is somewhat more straightforward. If your vehicle's middle seat only has a lap belt, you can still install the seat without the base. Unfortunately, this carrier doesn't feel that stable once installed and this impacted its installation score.
The canopy on the Aton 2 is small and the plastic visor doesn't provide much additional coverage.
Credit: Abriah Wofford
Ease of Use
The Aton 2 is more complicated to use than the average seat in this review.
The Aton 2 buckle and chest clip are both easy to use without requiring extra strength or dexterity.
Credit: Abriah Wofford
Harness
The buckle on the Cybex is easy to use and not as stiff as most competitors. It is easier to release than it is to buckle, but we still like it. The chest/retainer clip two sides mate up easily, and we didn't have any difficulty.
Tightening and loosening the harness straps on the Aton 2 is achieved with the strap and button on the foot of the carrier.
Credit: Abriah Wofford
The tightening strap on the harness is very stiff. We couldn't figure out why, but it is significantly harder to pull the strap. The padding on the shoulder straps also causes problems, and we couldn't get the harness tight enough for smaller babies. Loosening the harness is more manageable, and the button is easy to push and well-placed.
Adjusting the height of the shoulder straps requires rethreading the straps by removing them from a T splitter on the back of the seat. The straps can be detached from the splitter, pulled through the slots in the back, and then moved to a new slot and reattached back on the splitter. The straps have small loops that make them more challenging to get on and off than some competition. However, we prefer the non-rethread options where you can alter the height with the baby in the seat. The Cybex has three height options and one crotch strap position. The Cybex might not have enough adjustments to get the right fit for every baby.
Pressing the light grey buttons on either side of the handle allows you to rotate the handle on the Aton 2.
Credit: Abriah Wofford
Handle
The handle rubs the canopy when both are in the up position, but the shape is more comfortable than most of the carriers with sharper corners. Operating the handle requires pressing the buttons on both sides located near the pivot point and rotating to the desired position. The handle has four available positions and must be in the carry position for driving.
The smaller grey handle near the bottom on the base of the Aton 2 is the carrier release latch. The green portion on the handle indicates that the carrier is installed properly on the base.
Credit: Abriah Wofford
Carrier and Base Connection
The Cybex carrier is harder to install on its base than most of the competition. If it doesn't fall into place, you have to tilt it "just so" to make it click. We struggled with it on and off and felt it could be troubling with weight in the seat and a struggling baby to keep your cool. However, it has a visual indicator that the carrier is attached correctly, so once you manage to get it onto the base, you can feel confident it is attached. There is a green button on the grey release button on the front of the base that indicates a solid connection. In our experience, it never gave a false positive.
Releasing the carrier from the base requires depressing the green button (safety feature) on the grey release button then depressing the grey button on the front of the seat. After that, you can lift the carrier off the base. You'll need to remove the front of the base then lift the seat out. This process is more convoluted than the majority of the seats that have a release handle on the back of the carrier.
The Anton 2 user manual stores under the carrier seat and out of the way.
Credit: Abriah Wofford
LATCH Anchor and Manual Storage
The LATCH anchors store underneath the recline foot, and the recline foot needs to be extended to store or remove them. The trailing straps from the anchors can potentially get in the way of installing the carrier onto the base, so parents should be careful. The manual is stored under the carrier in a designated slot.
The energy absorption foam on the Aton 2 is the standard type across most of the competition.
Credit: Abriah Wofford
Comfort/Quality
The Cybex is a quality option with features for comfort. The Cybex has nice padding and soft fabric, but the padding is a little thin. The fabric is jersey knit and feels nice.
These factors help Cybex earn an overall nice fit and finish. The fabric fits the carrier well and gives it a sharp overall look. The canopy fits the frame well, opens and closes smoothly, and looks great. Unfortunately, the shell quality and durability aren't as impressive as the rest of the carrier. It feels thin and not as durable as some of the competition. It looks nice, but overall it isn't the quality we expect at this price point.
The canopy on the Cybex has a stiff plastic edge and is too small to protect baby from much.
Credit: Abriah Wofford
The canopy is small with a hard flip-out visor that helps provide more coverage, but it isn't the best. There is no peek-a-boo window, but you aren't likely to need one since the canopy is one of the smallest in the group.
The Cybex is below average for weight in the group, but it is still heavier than some of the competition.
Credit: Abriah Wofford
Weight
The Cybex weighs in at 9.32 lbs., which is below average for the group but still relatively light when you consider several are over 10 lbs. The weight for the Cybex is a good one for the group and didn't dissuade us in any way.
Stroller Compatibility
The Aton 2 is compatible with several nice choices, including the Editors' Choice UPPAbaby Cruz and the Top Pick for Versatility award winner, the UPPAbaby Vista. Both strollers are easy to use, have large canopies, and large storage bins with a weight capacity of 25 and 30 lbs, respectively. You can discover more potential combinations in our review of top-ranked stroller and car seat combos, where it excelled in combination with the UPPAbaby Minu Combo and the Thule Urban Glide 2 Combo, giving you a great lightweight choice or jogging stroller option.
Should You Buy the Aton2?
If you want the infant seat with the absolute best combined crash test results, the Aton2 is your seat. We like the Aton2 for its crash test results and ease of installation using the LATCH method performance. It offers enough comfort to keep little ones cozy and has a nice overall look. If you accept that it isn't compatible with many strollers and perhaps choose a baby carrier instead, we think there is much to love about this car seat.
What Other Infant Car Seat Should You Consider?
While the Cybex has impressive crash testing results, it isn't compatible with very many top-ranked full-size strollers, and it isn't the easiest to install with any method. It also sports a higher price, making it out of range for some families. If price and crash test results are your top priority, then the Chicco Keyfit 30 is one to consider. This seat earned the best HIC test result during crash tests, and it has a very budget-friendly price most families will love. The Chicco Keyfit 35 is also easier to install using both methods and has impressive crash-test results. It is also less expensive than Cybex and easier to use. Both Chicco options work with most of the best strollers.
