Convertible car seats
Rear-facing for infancy, then forward-facing with a harness. The 'keep them rear-facing longest' workhorse — many parents' one big seat.
Short answer: Going by each maker's manual, the highest rear-facing limit here is 50 lb (10 of the 24 seats). The forward-facing harness goes up to 65 lb, and high-back booster mode up to 120 lb on the 8 seats that have it. Useful life is 7 to 10 years where the manual gives one.
Weight limits and useful life, seat by seat
The weight ranges each maker prints in the seat's manual. Tap a seat to see it side by side with a similar model, with height limits and a link to its manual.
| Car seat | Rear-facing | Forward-facing harness | High-back booster | Useful life |
|---|---|---|---|---|
| Graco Extend2Fit | 4–50 lb | 22–65 lb | — | 10 yrs |
| Chicco NextFit Max | 4–50 lb | 22–65 lb | — | 8 yrs |
| Britax Marathon ClickTight | 5–40 lb | 22–65 lb | — | 10 yrs |
| Britax Boulevard ClickTight | 5–40 lb | 22–65 lb | — | 10 yrs |
| Nuna RAVA | 5–50 lb | 25–65 lb | — | 10 yrs |
| Clek Foonf | 14–50 lb | 26.5–65 lb | — | 9 yrs |
| Clek Fllo | 14–50 lb | 26.5–65 lb | — | 9 yrs |
| Diono Radian 3QXT | 4–50 lb | 22–65 lb | 40–120 lb | 10 yrs from purchase |
| Diono Radian 3RXT | 5–50 lb | 22–65 lb | 40–120 lb | 10 yrs from purchase |
| Cosco Scenera NEXT | 5–40 lb | 22–40 lb | — | 8 yrs |
| WAYB Pico | — | 26.5–50 lb | — | 7 yrs |
| Evenflo Tribute LX | 5–40 lb | 22–40 lb | — | — |
| Graco Contender Slim | 5–40 lb | 20–65 lb | — | 7 yrs |
| Graco SlimFit3 LX | 5–40 lb | 22–65 lb | 40–100 lb | 10 yrs |
| Britax Advocate ClickTight | 5–40 lb | 22–65 lb | — | 10 yrs |
| Britax Allegiance | 5–40 lb | 20–65 lb | — | 7 yrs |
| Maxi-Cosi Pria Max | 4–40 lb | 22–65 lb | 40–100 lb | 10 yrs |
| Chicco OneFit ClearTex | 5–40 lb | 25–65 lb | 40–100 lb | 10 yrs |
| Evenflo Revolve360 Slim | 4–50 lb | 22–65 lb | — | — |
| Safety 1st Grow and Go Sprint | 5–40 lb | 30–65 lb | 40–100 lb | 10 yrs |
| Chicco NextFit Zip | 5–40 lb | 22–65 lb | — | 8 yrs |
| Diono Radian 3R | 5–50 lb | 26.5–65 lb | 40–120 lb | 10 yrs from purchase |
| Graco Sequel 65 | 4–40 lb | 22–65 lb | — | 10 yrs |
| Cybex Eternis S | 4–50 lb | 22–65 lb | 40–120 lb | — |
Common questions
Which convertible car seats have the highest rear-facing weight limit?
The Graco Extend2Fit, the Chicco NextFit Max, the Nuna RAVA, the Clek Foonf, the Clek Fllo, the Diono Radian 3QXT, the Diono Radian 3RXT, the Evenflo Revolve360 Slim, the Diono Radian 3R and the Cybex Eternis S list a rear-facing limit of 50 lb, the highest here. The lowest is 40 lb (the Britax Marathon ClickTight, the Britax Boulevard ClickTight, the Cosco Scenera NEXT and 10 more). These are the makers' printed limits; your child's height also has to fit.
How heavy can a child be in the forward-facing harness?
Between 40 lb and 65 lb, depending on the seat. 21 of the 24 seats here with a forward-facing harness go up to 65 lb.
Up to what weight can these be used as a booster?
In high-back booster mode the maximum is between 100 and 120 lb; the Diono Radian 3QXT, the Diono Radian 3RXT, the Diono Radian 3R and the Cybex Eternis S go to 120 lb. A booster also needs the seat belt to fit your child, so check the height range in the manual too.
How long do convertible car seats last before they expire?
The manuals list a useful life of 7 to 10 years. Most count from the date of manufacture; the Diono Radian 3QXT, the Diono Radian 3RXT and the Diono Radian 3R count from the date of purchase. For 3 of the 24, the manual we cite gives no figure, so check the label on the seat. More by brand on car seat expiration.
Which of these convertible car seats are narrow enough for 3-across?
10 of the 24 are made narrow for fitting three across: the Clek Foonf, the Clek Fllo, the Diono Radian 3QXT, the Diono Radian 3RXT, the Cosco Scenera NEXT, the WAYB Pico, the Evenflo Tribute LX, the Graco Contender Slim, the Graco SlimFit3 LX and the Diono Radian 3R. Whether three fit depends on your back seat, so test-fit in your car.
Which of these convertible car seats can be used on a plane?
22 of the 24 are FAA-approved for use on aircraft: the Graco Extend2Fit, the Chicco NextFit Max, the Britax Marathon ClickTight, the Britax Boulevard ClickTight, the Nuna RAVA, the Clek Fllo, the Diono Radian 3QXT, the Diono Radian 3RXT, the Cosco Scenera NEXT, the WAYB Pico, the Evenflo Tribute LX, the Graco Contender Slim, the Graco SlimFit3 LX, the Britax Advocate ClickTight, the Britax Allegiance, the Maxi-Cosi Pria Max, the Chicco OneFit ClearTex, the Safety 1st Grow and Go Sprint, the Chicco NextFit Zip, the Diono Radian 3R, the Graco Sequel 65 and the Cybex Eternis S. Boosters are never approved for planes, because a plane seat has no shoulder belt.
Other stages: Infant · All-in-one · Booster · narrow seats for 3-across