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Garmin Forerunner 645 review

£248.00 Typical price

Test score %

Key features
  • Garmin OS

The Garmin Forerunner 645 is a GPS smartwatch aimed at those wanting to track their fitness activities. Its sibling, the Forerunner 645 Music, comes with internal storage for your music. So which of these expensive smartwatches is the right one for you? We challenged it in on the treadmill, on a woodland run and in the pool, and reveal all in our full review.

Included in our expert review
  • Pros and cons
  • What is it?
  • What can it do?
  • What's the setup like?
  • What's it like to wear and use?
  • How accurate is it?
  • Is there anything else I should know?
  • Should I buy it?
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Technical specifications

General

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 smartwatches
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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.

Make smarter choices

We have tested 50 smartwatches and found that there are 2 Don't Buys and 7 Best Buys.
Range of Smartwatch scores
  1. 44%
    Lowest score
  2. 67%
    Average score
  3. 76%
    Highest score
We'll show you where this model sits on the scale so that you can see how it compares to smartwatches we've tested
Try Which? for £1
You can cancel at any time

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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