In Depth Baby Product Reviews Led by a Pediatrician
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The Britax Marathon ClickTight utilizes the ClickTight system that makes installation virtually foolproof and removes the need for extra strength from the equation. We think the Marathon is a good-looking, high-quality convertible car seat that is very easy to use. The fabric is friendly and durable, the plastic shell is stylish and keeps straps contained, and the non-rethread harness adjustment can be made with your baby in the seat. However, it isn't the best choice for city dwellers as it is heavy and unsuitable for carrying very far. It is also expensive, and the crash test results are below the average in this review. The ClickTight installation may still have you considering this stylish option. If so, we suggest the Britax Boulevard ClickTight ARB, which scored significantly higher overall and only costs $10 more than the Marathon.
REASONS TO BUY
Easy ClickTight installation
Comfy quality
REASONS TO AVOID
Heavier
Price
Clip LATCH anchors
Below average crash test results
We are linking to the Marathon without the ARB. If you would like to create the same seat we tested in our review, you'd need to also purchase the Britax Anti Rebound Bar Accessory to pair with it.
Editor's Note: On December 21, 2021, we made additions to this review that include details on which seats we would recommend and what other options caregivers might consider.
Crash test results don't measure up to the impressive functionality of this seat
Great lightweight seat with excellent crash test results that is very easy to use
Rear-facing up to 50 lbs and the best crash results are a bonus to this budget-friendly seat
Budget-friendly, easy to use option with better crash test results make it a standout
Somewhat better than the average option with nothing extraordinary to sing about
Rating Categories
Britax Marathon Cli...
Britax Emblem
Graco Extend2Fit
Britax Allegiance
Graco SlimFit All-i...
Crash Test(35%)
4.5
8.0
8.5
8.0
6.0
Ease Of Install - LATCH(20%)
8.5
7.2
6.6
7.2
7.9
Ease Of Install - Belt(15%)
8.6
6.0
7.0
6.0
6.6
Ease Of Use(15%)
7.6
7.6
7.3
7.6
7.4
Comfort / Quality(10%)
8.6
7.4
5.8
6.8
5.8
Weight / Size(5%)
4.5
5.5
5.0
5.5
5.0
Specs
Britax Marathon Cli...
Britax Emblem
Graco Extend2Fit
Britax Allegiance
Graco SlimFit All-i...
Crash Test HIC Score
371
218
214
186
320
Crash Test Chest G Clip
48
42
40
43
43
Min/Max Rear Facing Passenger Weight
5 - 40 lbs
5 - 40 lbs
4 - 50 lbs
5 - 40 lbs
5 - 40 lbs
Min/Max Forward Facing Passenger Weight
20 - 65 lbs
20 - 65 lbs
22 - 64 lbs
20 - 65 lbs
22 - 65 lbs
Max Rear Facing Passenger Height
Child's head must be at least 1 in. below the top of the head restraint
Child's head must be at least 1 in. below the top of the head restraint
Child's head must be at least 1 in. below the top of the head restraint
Child's head must be at least 1 in. below the top of the head restraint
40" and the child's head must be at least 1 in. below the top of the child restraint.
Max Forward Facing Passenger Height
49" and the child's ears must be below the top of the head restraint.
49" and the child's ears must be below the top of the head restraint.
49" and the child's ears must be below the top of the seat shell.
49" and the child's ears must be below the top of the head restraint.
49" and the child's ears must be below the top of the seat shell.
Measured Rear Facing Seat Weight
27.9 lbs
18.8 lbs
18.7 lbs
18.5 lbs
18.6 lbs
Measured Forward Facing Seat Weight
26.9 lbs
18.8 lbs
18.7 lbs
18.5 lbs
18.6 lbs
Width
18.2"
18.9"
19.6"
18.8"
19"
Recline Positions
7
1 Rear Facing
2 Forward Facing
4 Rear Facing
3 Forward Facing
1 Rear Facing
2 Forward Facing
4 Total
2 Rear Facing
2 Forward Facing
1 Booster
Max Recline Angle
53°
42°
51°
42°
°
Shoulder Harness Positions
12
10
10
10
10
Crotch Strap Positions
2
2
2
2
3
Built in Lock Off
ClickTight System
Yes
No
Yes
No
Anti-rebound Device
Yes
No
No
No
No
Head Support
Yes
No
No
No
No
Newborn Insert
Yes
Yes
Yes
Yes
Yes
No Rethread Harness
Yes
Yes
Yes
Yes
Yes
Onboard Manual Storage
Yes
Yes
Yes
Yes
Yes
Level Indicator On Seat
Ball in Tube.
Line on Decal
Ball in Tube.
Line on Decal
Ball in Tube.
Foam Type
EPP
EPP
EPS
EPP
EPS
Seat Lifespan
10 yrs
7
7 yrs
7
10 yrs
Warranty
1 Year
1 Year
1 Year
1 Year
1 Year
Show full specification details ▼Hide full specification details ▲
Our Analysis and Test Results
Britax has been around for over 70 years in Europe. In 1939, British Accessories joined Romer in Germany in 1971 and launched their first safety seat in 1973. Britax went on to acquire other companies with a focus on safety seats in Australia and New Zealand. In 1990, Britax worked with other international organizations to develop the IsoFix, which became the LATCH method's foundation that emerged later. Britax brought its first safety seat to the US in 1996. They go on to introduce a convertible car seat, booster seats, and fan favorite infant car seats to the market. In 2002, LATCH anchors and continued improvements for safety and installation ensue. Britax also makes strollers and accessories.
Performance Comparison
The ARB like the one seen here on the Marathon ClickTight ARB is supposed to limit or prevent car seat rotation that can happen during a crash.
Credit: Abriah Wofford
Crash Test
Every seat for sale in the US must meet or exceed the Federal guideline minimums outlined in the FMVSS 213. However, some perform better during professional testing than others, indicating a possibility for an additional margin of protection. The Marathon results, as recorded in crash test dummy sensors, indicate that the Marathon results are basic and below the average for this group of products.
The head sensor result (HIC) for the Marathon was 371, where the maximum allowed is 1000, and the lower the result, the better. The chart below shows this result in comparison to the best HIC score in the group of 186 for the Britax Allegiance.
The Britax Marathon HIC result is almost twice that of the Essentials by Britax Allegiance where a lower result is preferable.
Credit: BabyGearLab, MGA Research
The chest clip result for the Marathon of 48 where 60 is the maximum allowed and lower is better, couldn't compare to the Clek Foonf result of 33.4.
Credit: BabyGearLab, MGA Research
The chest sensor results (g clip) for the Marathon was 48 where the maximum allowed is 60, and once again the lower result is better. The graph above shows the Marathon results compared to the best result in the group of 33.4 for the Clek Foonf.
The analysis of sensor results and the comparison of the data to the competition earned the Marathon a below-average result compared to the competition.
This seat also includes an anti-rebound bar (ARB) for rear-facing installation. Our preliminary test results with infant car seats indicate that the ARB does help reduce the sensor results and is, therefore, a potentially useful safety addition.
The LATCH strap on the Marathon threads high under the seat bottom but is easy to tighten using the ClickTight system that secures the seat by latching the seat bottom.
The LATCH installation of the MArathon in the rear-facing configuration includes threading the LATCH strap under the seat to use the ClickTight system.
Ease of Install - LATCH
The LATCH installation of the Marathon includes the ClickTight technology, which makes installation virtually foolproof. The seat installation involves threading the LATCH strap, attaching them to the car anchors, and closing the seat bottom to tighten the strap. If the ClickTight emblem on the front is once again horizontal, you know the installation is correct. Read the manual for complete instructions.
The more basic clip style LATCH anchor seems oddly placed on this higher end seat. However, it is safe, just harder to use than the push button style we prefer.
Credit: Abriah Wofford
The Marathon has basic clip-style anchors compared to the more comfortable push-button anchors we prefer. Both are safe, but the button style is easier to remove.
The level on the Marathon is a ball inside a plastic encasement. It helps parents determine when they have found the right angle for installation.
The Marathon has nine recline angles designed to help ensure the proper angle for installation is obtained based on the passenger's age and weight.
The Marathon has a ball-style level on the base of the seat. This level helps parents find the right angle for proper installation. The Marathon has seven different recline positions that help parents find the correct installation angle for the seat based on the weight and age of the passenger.
Installing the Marathon in the forward facing position using the vehicle belt uses the pathway furthest back on the seat. This path is the same as the one used for the LATCH strap.
The ClickTight installation system on the Marathon utilizes the same vehicle belt path as the LATCH strap.
Ease of Install - Belt
With the ClickTight methodology, the Marathon is easy to install by any method, including using the vehicle belt. While not as impressive as other ClickTight options, we suspect parents that don't install car seats for a living (like we do) won't notice the difference.
A quick peek under the Marathon seat bottom shows how the belt is threaded and makes it easier to understand how pressing the seat bottom down will tighten the strap automatically.
This photo shows the threading path for forward facing configuration of the Marathon installation using a yellow "belt" for clarity.
To install this seat in the front-facing configuration, you need to lift the seat up (above left), thread the belt across the back, and push the seat down to tighten the strap (above right). While not truly a belt lock-off (depending on seat installation method and placement, it is more of a tensioner), it does help stabilize the seat on the vehicle belt to avoid movement.
The rear-facing configuration of the Marathon incorporates the ClickTight seat bottom and an anti-rebound bar (ARB).
Credit: Abriah Wofford
For the rear-facing connection, the belt will thread lower on the base, but the seat bottom still works the same by raising and lowering to secure the seat in place.
The Marathon is very easy to use and tied with several other products, most of them made by Britax.
Credit: Abriah Wofford
Ease of Use
This Britax option is as easy to use as the other Britax products we tested in this review.
The Marathon ClickTight has a non-rethread height adjustment that works by sliding the headrest assembly up and down.
Credit: Abriah Wofford
Harness
The Marathon harness has 14 height positions and a two-position crotch strap, ensuring that almost every child can have a custom-fitted harness. The height adjusts with a non-rethread assembly that slides up and down with a squeeze of a button. This task can be accomplished with your baby in the seat for quick adjustments every time.
The Marathon buckle and chest clip are both stiff but still easy to use.
The harness release button is located above the ClickTight indicator emblem and is under a plastic flange that should prevent little ones from messing with the button.
The buckle and chest clip (above left) are somewhat stiff, like all of the Britax options. However, you can work them with one hand if you need to; they are probably stiff to help prevent older children from using them. There is a pull strap at the foot of the base to tighten the harness, and it loosens with a push of the button above the ClickTight emblem (above right). Both work well, and the strap doesn't require exceptional strength to use.
The Marathon has a plastic pocket on the base for tether storage to keep the strap out of the way when not in use.
The user manual of the Marathon stores in a pocket behind the seat back fabric. The location will prevent the manual from getting lost or in the hands of children, but if your child gets sick or spills a beverage the manual may suffer.
LATCH Storage
The unused LATCH anchors connect under the seat on the base to keep them out of the way. The tether hides in a plastic pocket of its own (above left) for a self-contained unit. The user manual is kept under the fabric on the seatback with a tab label. This location is handy and out of the reach of children, but it could get messy if there are spills or someone gets sick.
The cover fabric on the Marathon comes off in four pieces to reveal EPP foam for crash impact absorption.
Credit: Abriah Wofford
Cover
The cover of the Marathon comes off in four pieces and must be hand washed only. Britax is pretty serious about this point, as the manual has bold red letters telling you not to machine wash. It also must be line-dried, so you'll want to plan before washing it.
Britax uses durable yet friendly materials to create the Marathon, a pleasing and functional seat.
The Marathon has a hard plastic shell that keeps the LATCH straps and tether contained and out of the way.
Comfort/Quality
The Marathon ClickTight is a high-quality product with impressive quality and comfort. While this is the lower-level ClickTight, it is still significantly nicer than much of the competition (above left). With durable materials in a closed design, which works as expected, it is hard to find fault with this car seat. This option has less padding and a thinner headrest than the other ClickTight options in this review, but it is well-made, and the fabric is soft. The smooth fully contained seat (above right) gives the Marathon a sleek and clean overall look.
The bottom of the Marathon is relatively smooth with a rubber anti-slip rim and no sharp edges.
Credit: Abriah Wofford
The bottom of the seat has a rubber rim to help stabilize it, and there are no rough edges that could dent or damage your vehicle seat.
The Marathon is heavier in the rear configuration thanks to the anti-rebound bar, but either way it is heavier than the average product in this review.
Credit: Abriah Wofford
Weight
The Marathon is somewhat heavy, as are all of the ClickTight products we reviewed. It weighs 27.9 in the rear-facing configuration and is slightly lighter in the front-facing mode. This car seat is not the best option for parents looking to carry their seat or who plan to use it in the city on public transportation. The Marathon measures 18.2 inches wide, making it narrower than some but not as good as others that measure 17 inches. If you need to fit multiple people or safety seats in one row, this could be a contender, depending on your car.
Should You Buy the Marathon?
Probably not. In this review, several other car seats score higher in important metrics and overall, including two different Britax seats. While there is nothing wrong with the Marathon, perse, it isn't as impressive as some of the competition, and it sports a fairly high price for a lower score.
What Other Convertible Car Seat Should You Consider?
If you like Britax, the Britax Boulevard ClickTight ARB and the Britax Emblem earned higher overall scores, and your budget could be the deciding factor. The EMblem costs significantly less, has a higher crash test result analysis, and is still easy enough to install. While it isn't as flashy, it is a good seat for the price and one of the highest-scoring in the review. If you want something with thicker padding and a potential edge for comfort that is also easier to install, then the Boulevard could be the one for you; it is easier to install and has a slightly higher crash test analysis score.
