Best Diono Car Seats [All 14] All-in-one Convertible and Booster

What are the best Diono car seats? That depends on your needs. But it should be easier to answer this question because there are a few Diono car seats on the market. 

We’ll list and compare the Diono car seats with other brands. 

Very different from Graco which has released a ton of car seats (almost 40+ car seats we listed) to dominate the market, Diono focuses much on simplifying the lines and launching a handful of Diono car seats for choice.

Most belong to the Diono Radian series that is designed to fit 3 across multi-kids families.

Diono is really well-known for its Radian series of 3 across car seats. It should be the first car seat brand that takes 3 across into consideration and released that series to satisfy this need. I love this idea, though Diono is less popular than Graco because they are more expensive.

In this ultimate guide for the best Diono car seats, we reviewed the top 5 models in different types and for different use situations. We also list and compare all Diono Radian car seats belonging to the same group. Click the button below to explore the Diono car seats in that type or group – convertible, booster, and Radian series.

Top 5 Diono Car Seats

Best Diono Car Seats List

Best Budget

Diono Radian 3R

$199.99

Best Affordable

Diono Radian 3R 3-in-1 Car Seat
Diono Radian 3RXT

$349.99

Safest

Diono Radian 3QXT - purple car seat
Diono Radian 3QXT

$449.99

Best Booster

Diono Cambria 2 XL
Diono Cambria 2 XL

$129.99

Best Backless

Diono Solana 2 Latch Backless Booster
Diono Solana 2

$59.99

Convertible

All 10 Diono Convertible Car Seats Comparison

Booster

All 5 Diono Booster Car Seats Comparison

Radian Series

All 10 Diono Radian Series Car Seats Comparison

Diono Radian 3R - Cheapest Diono Radian Car Seat

Diono Radian 3R 3-in-1 Car Seat

Diono Radian 3R - 17"

Key Features
The Good
The Bad

$199.99

If you don’t have much budget for a Diono car seat, you shouldn’t skip the Radian 3R. It’s the cheapest one of the Diono Radian car seats. 

You can get a Diono Radian 3R at a price under $200. That’s far less expensive than other Diono Radian car seats. Its high-end siblings – 3RX, 3RXT, 3RXT Safe+, and the latest 3RXT Luxe, are priced $100-$200 more than the 3R. The 3QX and its premium versions in the same Radian series are $100-$300 more expensive than the 3R. 

Priced under $200, the Diono Radian 3R is one of the best cheap car seats. That’s a very good choice if you’re finding a low-priced 3 across car seat.

As an entry-level car seat of the Diono Radian series, the Radian 3R has very basic features. It does pass the crash tests and provides optimal protection it can.

The Diono Radian 3R has been built sturdily for its metal frame, making it a bit heavy. But this solid build should work well to enhance the protection. That’s the thought of most parents. 

Along with decent padding, it’s durable and lasts for good years. This matches its expectation to grow with your child. It’s an all-in-one car seat and can be used for three car seat stages including rear-facing, forward-facing, and booster.

In rear-facing mode, the Diono Radian 3R is good for babies between 5 and 50 pounds. Very few models have this 50-lbs top weight. As far as I know in our database, only Graco Extend2Fit and Britax One4Life can compete in this aspect. They all are good car seats for extended rear-facing. 

The 50-lbs should be suitable for tall babies to sit rear-facing for a longer time. Some toddlers aged around 4 years old could still use it in rear-facing until they are 44″ (this is the height limit of Diono Radian 3R in rear-facing) tall.

As a matter of fact, the 50-lb rear-facing weight limit is very commonly seen among the Diono Radian car seats. They all have the same 50 lbs for rear-facing, check the comparison table in below part.

However, if you planning to install it rear-facing, pay attention to the space the Diono Radian 3R will take. Its height is 28.5 inches. Install it rear-facing would take a bit more space from the front passenger if you place it on the window seats

This problem disappears when you switch the Diono Radian 3R to a forward-facing position. It has a narrow profile, especially in the bottom portion.

Diono Radian 3R Fit 3 Across

The widest point (mostly on the shoulder part) is just 17 inches, while the inside hip width is as narrow as 12 inches. This Diono car seat is good to fit 3 across. So do all Diono Radian car seats. The premium versions have the same design – a very slim fit to do 3 across.

The low profile is friendly for toddlers to climb in and out, no matter in 5-point harness mode or booster mode. The Diono Radian 3R is one of the best 5-point harness car seats with 120 pounds weight limit. The 120-lb is for the booster top weight, along with the 57″ height limit, making it a good car seat option for big kids at 7 or 8 years old.

Another point we love about Radian 3R and other Diono Radian car seats is the foldable design. Yes, Diono Radian car seats can be folded up from the bottom portion. This folding design makes the Diono Radian car seats the most portable option, even though they’re heavy.

The 3R is the most popular car seat from Diono Radian car seats, but it’s far less competitive than Graco SlimFit3 LX – another Graco car seat with the same fitting-3-across objective. We have compared the Diono Radian 3R versus Graco SlimFit3 LX if it’s a bit difficult for you to make a final decision between these two slim-fit car seats do 3 across.

Diono Radian 3RXT -

Diono Radian 3R 3-in-1 Car Seat

Diono Radian 3R - 17"

Key Features
The Good
The Bad

$349.99

The Radian 3RXT is an upgraded version of the 3R, with a few additions and a more expensive price. We’ll do a simple comparison of these two Diono Radian car seats and you’ll check if it’s worth paying $100+ more for the improvements.

First, we’d like to talk about the good things that remain in the upgraded 3RXT. That includes the narrow design (both 17″ wide) to fit three children across in the back row, low profile to easy in and out, folding body for easy carry, 50-lb rear-facing top weight, and 120-lb booster weight limit, high strength steel frame, solid build, and so on. 

What are the new features in Diono Radian 3RXT then? 

The Diono Radian 3RXT comes with an apparently large headrest and a 2-in-1 head-body insert. The headrest delivers great support if your child falls asleep in the car seat. It may be in the way if your child loves to get a window view. The head-body insert is good for small infants and toddlers, keeping them comfortable and safe in this Diono car seat.

Compared to the 3R, the Diono Radian 3RXT has one cup holder. That’s useful to store your child’s drinks or snacks. It can be removable if you need to do 3 across.

The invisible improvement is the harness positions. The Diono Radian 3RXT is packed with 12 positioning adjustments while the 3R only allows 10-position. Both have the same harness height of 16.5 inches (42 cm). More positions, more choices, and more fitting at different heights and ages.

The 3RXT has various versions available with different key features.

The 3RXT Safe+ has an anti-rebound bar and 6 layers of side impact protection; The 3RXT Luxe was designed with premium fabrics and a handy back seat organizer. Of course, they’re on the pricey side, around $400 or more.

Diono Radian 3QXT

Diono Radian 3QXT - purple car seat

Diono Radian 3QXT

Key Features
The Good
The Bad

$399.99

The Radian 3QXT is an upgraded version of 3RXT. The manufacturer boasts of 20 improvements comparing 3QXT versus 3RXT. 

But you’ll see the Diono Radian 3QXT is very similar to the Radian 3RXT Safe+. Both have six layers of side impact protection and an anti-rebound bar. Even the included infant insert is 95% similar to each other.

Both are also pricey over $400. 

Check the comparison between Diono Radian car seats below.

Diono Cambria 2 XL

Diono Cambria 2 XL

Diono Cambria 2 XL

Key Features
The Good
The Bad

$129.99

The Diono Cambria 2 XL is a very good booster seat. It’s roomy to grow with your child from 40 pounds to 120 pounds. 

That’s really a wide range for a booster, compared to those booster seats with a 100-lb top booster weight. The 40-pound is able to accommodate toddlers aged 4 or so. While the 120-pound is preferable for big kids until the day to get out of a car seat, making the Diono Cambria 2 XL is one of the best car seats for 7 years or older. The 63-inch top booster height is unbeatable among booster seats and good to last good years until your child is legally allowed to get out of a car seat.

It’s very understandable. The Diono Cambria 2 XL is a 2-in-1 booster seat and can be used in two modes: high back and backless. If you prefer better protection for small kids (of course should be at least 4 years old), use it in the high back mode; for big kids who can have a good upright sitting in a car seat, backless is optional.

This Diono car seat is well-designed to match its size limit. It’s tall and wide. The height is 29 inches. It provides 6 positioning adjustments, allowing you to find the most comfortable fit for your child currently or in the future when they grow bigger.

Measuring 20-inch wide at the shoulder portion, the Cambriax 2 XL is not a narrow car seat. It’s not as narrow as its Radian series.

So if you want to use to do three across, you’ll be disappointed in it. It reduces the width if removing the backrest and turning it into the no back mode, but fitting three across is impossible because the armrest portion is 18.5 inches wide.

It’s pretty simple to install this Diono car seat using the LATCH connectors. Just attach the hooks on the bottom of the booster seat to the car’s seat. Once the seats are sturdy and strapped in correctly (following the user manual instructions), the Cambria 2 XL should be installed tightly.

It has two pull-out cup holders on both sides to fit juice boxes and snacks, and even toys. Each cup holder has two slots.

There are multiple colors available for choice. Pink is good for toddler girls. Check our post on pink-colored car seats for girls if you need them.

The Cambria 2 XL is lightweight, weighing only 12.8 pounds with the backrest on. It’s a good light car seat for travel. But you should not use it on a plane, because all booster seats are not approved for aircraft use. 

Diono Solana 2 XL

Diono Solana 2 Latch Backless Booster

Diono Solana 2 XL

Key Features
The Good
The Bad

$59.99

The Solana 2 XL is another popular Diono car seat that has the most reviews (4000+). It’s a backless booster. 

Without a doubt, it’s lightweight and portable, and good for travel. But it is not able to do 3 across. The widest part lies on the armrest and is 18.5 inches.

There are multiple various versions for option. Some with LATCH connectors for installation; some with seat belt installation attachments. If you have more than one kid in a booster seat, the bundle of two Solana XL booster seats is available as well. This will save money.

The Solana 2 XL also has two tuckle-away cup holders that are similar to Cambria XL’s. That’s good for carrying your child’s drinks, snacks, and toys.

Diono All-in-one Car Seats Comparison

Model Weight / Height Limits Recommended Age User Manual
Radian 3R 120 lbs/ 57" Newborn- 8 years old User Manual
Radian 3RX 120 lbs/ 57" Newborn- 8 years old User Manual
Radian 3RX Safe+ 120 lbs/ 57" Newborn- 8 years old User Manual
Radian 3RXT 120 lbs/ 57" Newborn- 8 years old User Manual
Radian 3QX 120 lbs/ 57" Newborn- 8 years old User Manual
Radian 3QXT 120 lbs/ 57" Newborn- 8 years old User Manual
Radian 3QXT+ 120 lbs/ 57" Newborn- 8 years old User Manual

Diono Booster Seats Comparison

Model Weight / Height Limits Recommended Age Online User Manual
Cambria 2 XL 120 lbs/ 63" 4 - 10 years old User Manual
Monterey XT 120 lbs/ 63" 4 - 10 years old User Manual
Monterey XT LATCH 120 lbs/ 63" 4 - 10 years old User Manual
Solana2 120 lbs/ 63" 4 - 10 years old User Manual
Monterey 4DXT 120 lbs/ 63" 4 - 10 years old User Manual
Everett NXT 120 lbs/ 63" 4 - 10 years old User Manual
Monterey® 5iST FixSafe™ 120 lbs/ 63" 4 - 10 years old User Manual

Diono Radian Car Seats Comparison

The Radian series have the same upper weight and height limits for rear-facing, forward-facing, and booster. 

And the Diono Radian car seats rank top on the best rear facing car seats 50 lbs.

Model Weight Limits Height Limits Recommended Age SIP User Manual
Radian 3R RF:5-50 lbs; FF: 22-65 lbs; Booster: 40-120 lbs RF: ~44"; FF: ~49"; Booster:57" Newborn- 8 years old 2 layers User Manual
Radian 3RX RF:5-50 lbs; FF: 22-65 lbs; Booster: 40-120 lbs RF: ~44"; FF: ~49"; Booster:57" Newborn- 8 years old 2 layers User Manual
Radian 3RX Safe+ RF:5-50 lbs; FF: 22-65 lbs; Booster: 40-120 lbs RF: ~44"; FF: ~49"; Booster:57" Newborn- 8 years old 2 layers User Manual
Radian 3RXT RF:5-50 lbs; FF: 22-65 lbs; Booster: 40-120 lbs RF: ~44"; FF: ~49"; Booster:57" Newborn- 8 years old 2 layers User Manual
Radian 3QX RF:4-50 lbs; FF: 22-65 lbs; Booster: 40-120 lbs RF: 18-44"; FF: ~49"; Booster:57" Newborn- 8 years old 6 layers User Manual
Radian 3QXT RF:4-50 lbs; FF: 22-65 lbs; Booster: 40-120 lbs RF: 18-44"; FF: ~49"; Booster:57" Newborn- 8 years old 8 layers User Manual
Radian 3QXT+ RF:4-50 lbs; FF: 22-65 lbs; Booster: 40-120 lbs RF: 18-44"; FF: ~49"; Booster:57" Newborn- 8 years old 8 layers User Manual

When do Diono car seats expire?

How long Diono car seats are good mainly depends on the types.

Diono all-in-one convertible car seats are good for 10 years of use since the date of manufacture.

Diono booster seats are good for 8 years from the date of manufacture. 

Same as Graco, the expiration date of Diono car seats are not printed directly on the white sticker. You can find the manufacture date only on that label, which is commonly sticked on the back or side of the Diono car seats. Then need to do a simple calculation to finally get the expiry date. 

Visit this post on Diono car seats’ expiry date to learn more details.

Where to install the Diono Car Seats?

The safest position to install the Diono car seats should be the center seat in the back row.

But if you can’t install a Diono car seat PROPERLY in the rear middle, try to place it on either window seat. Proper installation is more important than the seating position.

According to the study published in Pediatrics, for newborns to 3 years old toddlers, with all installs being equal or proper installation, sitting in the rear center seat is 43% safer than sitting on the window side in the back seat. 

A few parents complain about the installation of a Diono car seat, especially in the rear-facing direction, is more difficult than other brands like Graco, Britax, and Chicco. If this situation happens to you, remember to install the Diono car seats on the spot where you can achieve a proper and tight installation.

Diono Car Seats Recall List 2022

We draw this list of recalled Diono car seats in 2022 based on the data of the NHTSA (National Highway Traffic Safety Administrator).  You can check what Diono car seats have been recalled and confirm if your Diono car seat has been on the list or not.

We do this list to help you avoid buying a car seat that has been through a recall event. 

It’s best to register the Diono car seat once you receive it. You can do this via the user manual, or contact the manufacturer’s customer service.

DIONO RADIAN R120

DIONO OLYMPIA

DIONO RADIAN RXT

DIONO PACIFICA

DIONO RADIAN R100

DIONO RAINIER

DIONO CAMBRIA 2

If you want to know all Diono car seats that have been recalled, please go to the NHTSA recall page and type Diono for search.

Diono Car Seats Buying Guide

If you’re trying to select a Diono car seat, you may read this guide to know which Diono car seat best suits your needs. Of course, you can use these tips to compare and find any other car seats from other brands.

Safety

Safety is the number one thing when finding a Diono car seat. This is also the main reason to purchase a car seat for your child.

You can be assured that all Diono car seats and other car seats that are for sale in America are manufactured and crash tested under federal safety standards – FMVSS 213.

Most car seat brands will add extra safety features for enhanced protection. So does Diono.

All the Diono car seats have a sturdy metal frame, except those backless boosters. Along with plently of cushion around the backrest and the bottom portion for energy absorption, the Diono car seats have a solid build that delivers optimal protection.

Side impact protection is a good point. The more layers, the more protective, the better. 

Most Diono car seats (except backless models) have two layers of side impact protection. Some higher-end Radian car seats have six or eight layers, like the 3RXT Safe+ and 3QXT

That’s the most layers of side impact protection I’ve seen among the reviewed 50+ car seats, beating other car seat brands.

Install

Improper car seat installation means no protection in a crash and may result in fatal death for a toddler if that happens.

For us, we believe the proper installation is more important than bonus safety features under the condition that all the car seats meet the FMVSS 213.

There are two methods to install the Diono car seats: use the LATCH or seat belt. NEVER use both.

Some Diono car seats have SuperLATCH connectors for installation. That would be easier than using the common LATCH attachments. But not all Diono car seats have this feature, at least not the Diono booster seats.

Using the seat belt to install the Diono car seats would be a bit more difficult than using the LATCH. They don’t have a seat belt lock system for an easy and tight installation. Practices make perfect.

Size Limits

This is my favorite place. You can choose a car seat with great size limits to save money without compromising safety. 

Diono car seats have the best size limits.

All the Diono Radian car seats are all-in-one and have a 50-lb weight limit for rear-facing, good for keeping your child to 4 years old. They all have a 120-lb booster weight limit. Some high-end Radian car seats have a 63 inches height limit.

All the Diono booster seats allow big kids to sit until they reach 120 pounds or 63″ tall.

Fabric

This is the last but not least important factor. It means a lot to both children and parents.

Machine washable fabric does not only imply comfort for your child but also is convenient for busy parents.

You won’t want to hand wash the seat pad, right? Luckily, all the Diono car seats come with machine-washable fabrics.

Warranty

All the Diono car seats have a standard 12-month warranty. But you can effortlessly extend the warranty to 36 months by registering the car seat when you receive it. That’s good for you.

Other brands do not have this extendable warranty service even if you register the car seat.

Diono Car Seats FAQs

Are Diono car seats good?

Diono car seats are good for their streamlined design and great safety features. 

The Diono Radian car seats have narrow profiles so you will be able to do 3 across with ease. Plus they have provided multiple color options so that you can simply choose the suitable one for boys or girls. The bright pink color can be found in a lot of Diono car seats.

What is the difference between the Diono car seats?

Diono has only a few car seats on the market. The main Radian series has a handful of car seats with a small difference between high-end models. But great improvements can be found between the entry-level model Radian 3R and the premium model Radian 3QXT

The Diono car seats in the Radian series are all-in-one car seats. They all have a great size limit and a slim-fit design. So the main difference would be the extra safety features and certainly the price.

Check out the difference between the Diono Radian car seats in the above comparison table.

What is the safest Diono car seat on the market?

The safest car seat on the market is the Diono Radian 3QXT and 3QXT+. Both have 8 layers of side impact protection plus an anti-rebound bar.

What are the weight limits for the Diono convertible car seats?

The Diono convertible car seats belong to an all-in-one car seat type. They all last for three car seat stages.

In rear-facing, the Diono convertible car seats have a weight limit of up to 50 pounds, making them the best extendable rear-facing car seat for 2 years old, 3 years old, or even 4 years old.

You may wonder what’s the height limit for rear-facing. You can’t find this data in a product description but in the user manual. The Diono Radian car seats can fit your child in rear-facing until they are 44 inches tall. This top height makes the Diono Radian car seats a good car seat option for tall babies.

In forward-facing with the 5-point harness, the Diono convertible car seats are good for children up to 65 pounds and 49 inches tall. They are good car seats for fitting kids between 4 and 5 years old in the 5-point harness mode.

In booster mode, the Diono convertible car seats are suitable for big kids up to 120 pounds.

How do you install the Diono high back booster seat?

The Diono high-back booster seat can be installed forward-facing only. If it has LATCH connectors, you can install it using the LATCH. Otherwise, using the seat belt is the only way to install the Diono high-back booster seat. 

The best way to install the Diono high back booster is to follow the user manual. 

What other features does the Diono Radian car seats have?

They have cup holder, great headrest, head-body insert, and memory foam plus comfy side walls (except the 3R).

Some high-end Diono Radian car seats have six or eight layers of side impact and an anti-rebound bar.

Which car seats would be good alternatives for Diono car seats?

There are many good child car seats on the market today. Here’s a shortlist to choose from Graco car seats, Britax car seats, Chicco car seats, and more. The Diono car seats are well-known for the Radian series, which was designed to fit 3 across. The Graco SlimFit3 LX is a good alternative.

But the six or eight layers of side impact protection used in the Diono Radian 3RXT and 3QX and its siblings are unbeatable, and no alternatives.

Can you fit three across these best Diono car seats?

Yes, these Diono car seats allow you to do 3 across since they have a narrow profile. However, keep in mind that only the Radian series can do 3 across. 

The booster seats, including the backless models like the Solana are not good to do 3 across. They are 18.5 inches wide at the armrest portion. 

You can check the car’s width interior and compare it with the Diono car seats to find one that fits three across. Also make sure you check the manual and the installation videos before you install. Finally asked for help from a child passenger safety technician if you’re stuck.

Are these best Diono car seats safe?

You can’t go wrong with Diono car seats. They have pass the crash tests under the federal safety standards #safety to keep your child protected. 

They all are equipped with EPS foam, memory foam, full steel frame, and thick padding. The EPS foam means that it will absorb car accident energy. The steel frame will disseminate the crash energy for keeping your child protected no matter what. The headrest provides not only the comfort but also an excellent support.

How easy is it to clean these best Diono car seats?

These Diono car seats are made of machine-washable fabrics. They have a seat cover that can be easily removed and cleaned with the washing machine. 

For the harness and buckle, you’d better follow the user manual for cleaning.