ASK FOR i-Size

The Smarter Way to Ride

Choosing the safest car seat doesn’t have to be complicated... when you buy an i-Size certified car seat that meets the highest ECE R129 safety standards, you’re investing in a seat that offers a guaranteed fit in i-Size approved vehicles, has an intuitive installation, and is tested by the most current European car seat standards.

ECE R129 Safety Enhancements

Child in car seat

side impact certified

Ensures the best head, neck, and all over protection with standardised side impact testing. Older standards, like ECE R44, did not include side impact!

more info

Child in car seat

rearward facing longer

Mandates rearward-facing travel to a minimum of 76 cm / >15 months — which allows baby’s neck to develop and strengthen before switching to forward-facing travel.

more info

Cart seat being tested in laboratory

smartest dummies

ECE R129 testing uses all new, advanced technology crash test dummies with more sensors than older dummies — to better simulate a child’s fragile body more accurately.

more info

Child in car seat

better fit formula

ECE R129 determines car seat usage based on a child’s height instead of weight — ensuring a more accurate fit for growing children.

more info

iSize certification label

i-Size certification

i-Size is an enhancment of ECE R129, which mandates car seats to use ISOFIX installation with internal harness usage and offers a guaranteed fit in i-Size approved vehicles.

more info

more info

i-Size logo

Ride with Confidence.
Ride with “i”

To ensure you’re purchasing a car seat that meets the highest ECE R129 safety standard and has i-Size certification, simply look for the ”i” in front of any of our car seat names (Ex: i-Prodigi™). You can also check the specifications section on our website product pages to confirm i-Size and ECE R129 certification.

ECE R129 or i-Size... what’s the difference?

It’s common to think ECE R129 and i-Size mean the same thing because many brands and publishers have used the terms interchangeably. Including us! While ECE R129 and i-Size car seats undergo the same side-impact testing with advanced crash-test dummies, require mandatory rear-facing until 15 months, and use height instead of weight for proper usage; the terms differ in two key areas:

ECE R129 logo

ECE R129

European safety regulation

ECE R129 refers to the most recent and safest European safety regulation that controls the manufacturing of car seats. The ECE R129 safety regulation provides better side-impact protection, requires rear-facing for longer, and makes it easier to find the best-fitting car seat for your child.

i-Size logo


Enhancement of ECE R129

i-Size, on the other hand, is an enhancement of ECE R129 that makes it easier to confirm your car seat’s compatibility with any i-Size approved vehicle — reducing the risk of installing your car seat incorrectly. The idea behind i-Size is that all car seats will eventually fit in all cars. While all i-Size car seats meet the ECE R129 testing standards, not every ECE R129 car seat is an i-Size compatible seat.

For extra peace of mind when shopping for a car seat, ask for a car seat that meets the ECE R129 safety regulation and look for the yellow i-Size icon to verify that it’s suitable for your i-Size approved vehicle. Still have questions? Check out our FAQ section below!

ECE R129 & i-SIZE Q&A

Like all parents, we know you are focused on keeping your child as safe as possible. We also know you might have so many questions and so little time to research. Read on below for answers to some of your more complex questions about ECE R129 and i-Size.

What is ECE R129?

ECE R129 is the new EU standard for car seat safety that was ratified in July 2013. ECE R129 has been running parallel to the older testing standard, ECE R44/04, since then. ECE R129 will replace ECE R44 entirely as the only approved EU car seat testing standard as of September 1, 2023. Only ECE R129 car seats will be legally sold to the consumers from September 2024 and onward.

How will ECE R129 keep my child safer?

ECE R129 regulations promote longer rear-facing by requiring children travel rearward up to at least 15 months. Additionally, ECE R129 has introduced the first-ever side impact testing standards, which will improve protection of the child’s head and neck. While Joie always took the initiative to test for side impact, the new regulations will ensure standards are met industry-wide.

ECE R129 makes use of the most high-tech crash test dummies available, called “Q” dummies. Not only has the sensory technology improved to test for greater sensitivity, it also features more sensors on fragile areas of the body. This means we have a better understanding of what happens during a crash, allowing us to improve the design of our car seats.

The previous “newborn” dummies (“P” dummies) were made only of fabric and did not have sensors. The new “Q” newborn dummies now feature 4 sensors in critical locations: the head, neck, thorax and pelvis. These sensors are extremely delicate, designed to simulate the fragility of a newborn body.

Since the ECE R44 standards were established the cars we drive have changed dramatically, and so has our knowledge about what happens during an accident. ECE R129 is the newest, safest standard for testing car seats. It introduces a more accurate fit for child, side-impact standards, and rearward-facing longer. ECE R129 also makes use of the latest dummy sensory technology designed to more accurately simulate a child’s fragile body. This means ECE R129 car seats are designed better, safer and stronger.

Is ECE R129 the same thing as i-Size?

Not quite! All i-Size car seats are tested to the ECE R129 safety but not all ECE R129 car seats have i-Size certification.

i-Size in an enhancement of the ECE R129 safety standard that makes it easier to confirm your car seat’s compatibility with any i-Size approved vehicle — reducing the risk of installing your car seat incorrectly. The idea behind i-Size is that all car seats will eventually fit inall cars.

Why is rearward-facing up to 15 months safer?

Research shows that a baby’s neck is not yet strong enough to support a baby’s heavy head until at least 15 months. i-Size doesn’t allow forwards-facing travel until a minimum of 15 months to ensure the child’s neck has developed the strength needed to support an average forward collision. Due to the increased security of travelling rearward for as long as possible, many Joie car seats exceed the ECE R129 regulation and promote rearward facing up to approximately 4 years.

Why is side-impact testing and standardisation so important?

The ECE R44 standard does not include side-impact testing, though we all know that accidents happen from all sides. While Joie has always maintained the strictest criteria for side-impact protection, the new ECE R129 standard enforces mandatory side-impact performance criteria industry-wide.

What vehicle features does i-Size require?

Vehicles must be equipped with ISOFIX and adhere to stricter space-to-seat ratio requirements.

Check your vehicle manual to ensure that your vehicle meets i-Size regulations. In most cases, if your vehicle is equipped with ISOFIX, it may be i-Size compatible already.

Are all R129 seats i-Size?

Not quite. All i-Size car seats are ECE R129 certified, but not all ECE R129 certified seats are i-Size. To qualify as i-Size, the child seat must fulfill additional requirements beyond a classic ECE R129 certified seat. i-Size makes it easier to confirm your child seat’s compatibility with any i-Size approved vehicle — reducing the risk of incorrect install. Additionally, i-Size car seats must fit within a specific box within your vehicle, but they’ve still been rigorously tested to ECE R129’s standards — so rest assured they are just as safe for your baby.

  • Child in car seat
  • Child in car seat
  • Cart seat being tested in laboratory
  • Child in car seat
  • iSize certification label