46mm case size
RUN AT A HIGHER LEVEL
You’re making strides. Now, let’s take the next step. Get the training and recovery insights you’ll need to notch your best time yet.
READY FOR THE LONG RUN
Get an uninterrupted picture of your daily health and nightly sleep with up to 12 days of battery life in smartwatch mode and up to 26 hours in GPS mode.
(ALMOST) AS LIGHT AS A FEATHER
With its sleek design and 1.4 oz weight, you’ll almost forget you’re wearing Forerunner 255S — even when you’re asleep.
Featuring easy-to-use buttons and a silicone band, this watch is ready to wear — and tear — with durable Corning® Gorilla® Glass 3.
Receive an overview of your sleep, recovery and training outlook as soon as you wake up — alongside HRV status and weather. You can even customize your report to show you what you want to see.
Gain a deeper understanding of your overall health, recovery and training performance through heart rate variability while you sleep, based on technology developed by our Firstbeat Analytics™ team.
BUILT-IN SPORTS APPS
Tap into 30+ built-in activities, including the triathlon and open-water swimming profiles — new to the Forerunner 255 series. For races and brick workouts, transition to the next activity with a single button press.
Get ready for your next race with training tips, personalized daily suggested workouts and completion time predictions based on course details, weather and performance.
DAILY SUGGESTED WORKOUTS
View your entire week of daily suggested workouts, which adapt after every run to match your performance and recovery as well as the races coming up in your Garmin Connect™ smartphone app calendar.
Free adaptive training plans include 5K, 10K and half-marathon programs, featuring guidance from expert coaches that adapt to you and your goals.
When using a Running Dynamics Pod or HRM-Pro ™ monitor, get a continuous measurement on your wrist of how much power you’re applying to the road as you run, so you can manage your effort.
Know how long to recover before your next high-effort workout based on your latest training as well as overall stress, sleep and daily activities outside of workouts.
To help you plan your race day strategy, this feature offers GPS-based pace guidance for a selected course or distance, so you can tailor your efforts to what’s ahead.
Using new indicators such as HRV status, your recent exercise history and performance, get an easy insight into your overall effort — and whether you’re training productively, peaking or strained.
See your training history, and compare the intensity of your recent workouts to the optimal range to help improve your fitness.
See how your workouts influence your endurance, speed and power with aerobic and anaerobic training effect feedback.
While you run, get an analysis of your pace and heart rate for a real-time assessment of your current ability to perform.
When using a Running Dynamics Pod or HRM-Pro monitor, the Forerunner 255S watch measures crucial running metrics such as cadence, stride length, ground contact time and balance, and more — while comparing to others in the Garmin Connect app.
Create or find existing courses in the Garmin Connect app, so you’ll never run out of places to run. Or plan one on other platforms such as Strava and Komoot, then automatically sync them to your Forerunner.
VISUAL RACE PREDICTOR
Based on your running history and overall fitness level, get an estimate of what your pace could be for a 5K, 10K — or even a marathon. Plus, trend data highlights your training’s impact over time.
Mix up your training with different types of workouts. Free HIIT, strength, cardio, yoga and Pilates workouts come preloaded on the watch, and you can download more from the Garmin Connect app.
WRIST-BASED HEART RATE
The watch constantly samples your heart rate2 with our latest-generation heart rate sensor and will alert you if it stays too high or too low while you’re at rest. It also helps gauge how hard you work during activities — even while swimming.
BODY BATTERY™ ENERGY MONITORING
Track your body’s energy levels so you can find the best times for activity and rest2.
IMPROVED SLEEP MONITORING AND SLEEP SCORE
Understand how your body is recovering — and get ready for training — with our improved sleep monitoring feature. After waking up, you’ll receive a sleep score, as well as breakdown of your sleep stages, Pulse Ox3 and respiration, alongside detailed insights for improved sleep quality.
PULSE OX SENSOR
This wrist-based Pulse Ox sensor3 monitors blood oxygen saturation levels to support advanced sleep monitoring and altitude acclimation.
WOMEN’S HEALTH TRACKING
Use the Garmin Connect app to track your menstrual cycle or pregnancy. Log symptoms, get exercise and nutrition education, and more. Even see and log details on your wrist with the Women’s Health Tracking app.
Our intensity minutes feature tells you when during the day you earned them and during what activity.
Find out if you’re having a calm, balanced or stressful day. Relax reminders will even prompt you to do a short breathing activity when the watch detects that you’re feeling stressed.
HEALTH SNAPSHOT™ FEATURE
Log a 2-minute session to record key stats, including heart rate2, heart rate variability, Pulse Ox3, respiration and stress. Then generate a report with those stats to share via the Garmin Connect app on your compatible smartphone.
MULTI-BAND GNSS SUPPORT
Access multiple global navigation satellite systems, and get access to multiple frequencies sent by navigation satellites for improved accuracy in areas where GNSS signals are reflected, weak or typically don't penetrate — giving you superior accuracy for how far and how fast you’ve run — even in challenging environments.
MUSIC ON YOUR WRIST
Download up to 500 songs plus playlists from your Spotify, Deezer or Amazon Music accounts (subscription may be required).
GARMIN PAY CONTACTLESS PAYMENTS
Breeze through checkout lines with Garmin Pay contactless payments1 through participating providers.
Receive emails, texts and alerts right on your watch when paired with your Apple® Android™ smartphone. You can even respond to texts if you have an Android phone.
SAFETY AND TRACKING FEATURES
If you feel unsafe or if your watch senses that an incident occurred, the Assistance and incident detection features4 send your location to emergency contacts. Incident detection is enabled by default for select activity profiles only.
Use LiveTrack to let friends and family follow your real-time location4 and even view your entire preplanned course. Rest assured that your loved ones know exactly where you’re running.
GARMIN CONNECT APP
See your health and fitness information, connect and compete with friends, sign up for challenges to earn badges and more — all in one free, zero-subscription app.
CONNECT IQ™ STORE
Download custom watch faces, add data fields, and get apps and widgets from the Connect IQ Store app downloaded on your compatible smartphone.