Trusted Reviews is supported by its audience. If you purchase through links on our site, we may earn a commission. Learn more.

Garmin Forerunner 45 and Forerunner 945: Everything you need to know

Garmin has revealed a new range of GPS running smartwatches: Forerunner 45, Forerunner 45S, Forerunner 245, Forerunner 245 Music, and Forerunner 945.

Launched on April 30, the new range caters for those who have just taken up running and only need the basics, plus the elite pacesetters who require the most accurate equipment.

All of the new wearables feature an always-on sunlight-readable display, GPS, all-day tracking, smart notifications, and a wrist-based heart rate tracker. But with prices ranging from £169.99 ($199.99) to £549.99 ($599.99), specifications vary considerably among the models – read on for the full breakdown.

Forerunner 45 and Forerunner 45S

The only difference between these two watches is the size – the 45S has a 39mm case suitable for those with smaller wrists, whereas the standard Forerunner 45 has a 42mm case. Both watches feature 12 activity profiles (including running, cardio, cycling, and yoga), and they are designed to be worn 24/7, capable of monitoring daily steps, distance, calories burned, and sleep. It uses the data to give you insights such as all-day stress monitoring, and energy monitoring.

Claimed Battery Life: 7 days in smartwatch mode, 13 hours in GPS mode

Price: £169.99 ($199.99)

Forerunner 245 and Forerunner 245 Music

These two entries are updates to Garmin’s most popular running smartwatch, the Forerunner 235. The difference between the two new models is that the Music version holds up to 500 songs (by transfer from computer), and allows synchronisation from streaming playlists on Spotify.

Both watches monitor VO2 Max, and can adjust training status for heat, recovery time, and aerobic and anaerobic training effects.If you use a compatible heart rate strap you can view all six of Garmin’s running dynamics on the watch (including ground contact time, cadence, and stride length). After your workout it can measure how oxygen is being absorbed with its wrist-based Pulse Ox sensor 4.

Claimed Battery Life: 7 days in smartwatch mode, 24 hours in GPS mode, 6 hours in GPS mode with music

Price: £249 ($299.99) for the standard version; £299 ($349.99) for the Music version

Forerunner 945

The 945 is a high-end running and triathlon smartwatch, which offers full-colour onboard maps, ability to pay with the Garmin Pay app, and the capacity to hold 1000 songs or synchronise from Spotify.

The training load focus feature allows you to sort your recent training history based on activity structure and intensity, and like the 245 series you can view Garmin’s six running dynamics on the watch if you use a compatible heart rate strap. This watch features further built-in profiles for activities such as skiing, hiking, and golfing, and also offers the Pulse Ox4 sensor to check your oxygen absorption.

Claimed Battery Life: 2 weeks in smartwatch mode, 36 hours in GPS mode, 10 hours in GPS mode with music

Price: £519.99 ($599.99)

Will you buy one of the new Garmin Forerunner smartwatches? Let us know on Twitter at @TrustedReviews

Why trust our journalism?

Founded in 2004, Trusted Reviews exists to give our readers thorough, unbiased and independent advice on what to buy.

Today, we have 9 million users a month around the world, and assess more than 1,000 products a year.

author icon

Editorial independence

Editorial independence means being able to give an unbiased verdict about a product or company, with the avoidance of conflicts of interest. To ensure this is possible, every member of the editorial staff follows a clear code of conduct.

author icon

Professional conduct

We also expect our journalists to follow clear ethical standards in their work. Our staff members must strive for honesty and accuracy in everything they do. We follow the IPSO Editors’ code of practice to underpin these standards.