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Diono Radian 5 review

Product alert

The Diono Radian 5 multi-group seat is approved for use with babies from birth up to 25kg, which is around seven years old. The regulation this seat is approved to does not include a side impact crash tests. All car seats we review include a side impact crash test. In our tests, a combination of poor frontal crash-test results and how difficult it is to install means the score is limited to 20% and it's a Don't Buy car seat. A good car seat should protect well in all the modes it's designed to be used in and be easy to install, to avoid error.

Further reading

Use our tools, tips and advice to protect you and your home How we test child car seats
£180.00 Typical price

Test score %

Key features
  • Group 0/1/2
  • Multigroup
  • Extended rear-facing
Reviewed

Diono's Radian 5 is a unique extended rear-facing child car seat designed to last from birth up until your child reaches 25kg in weight, or about seven-years old. It can be used rear-facing with your child strapped in using the harness up to 25kg, too, so this child car seat could be ideal if you have a larger than average child. Is it easy to install and how safe is it? Read our safety alert to find out why it's a Don't Buy.

Included in our expert review
  • Pros and cons
  • What is it?
  • How safe is it?
  • Is the seat easy to fit?
  • Is the seat comfortable?
  • Is there anything else I should know?
  • Is there anything else I should watch out for?
  • Statement from Diono
  • Should I buy it?
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Test results

The overall Which? test score is made up of the following star ratings, all determined by our rigorous lab tests.

Find out how we test child car seats
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We have tested 193 child car seats and found that there are 20 Don't Buys and 48 Best Buys.
Range of Child car seat scores
  1. 0%
    Lowest score
  2. 65%
    Average score
  3. 82%
    Highest score
We'll show you where this model sits on the scale so that you can see how it compares to child car seats we've tested
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Put us to the test

Our Test Labs compare features and prices on a range of products. Try Which? to unlock our reviews. You'll instantly be able to compare our test scores, so you can make sure you don't get stuck with a Don't Buy.

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