Garmin Forerunner 255 GPS Running Smartwatch - Long Battery Life

In this review the Garmin Forerunner 255 shows itself as a focused running smartwatch for athletes who want reliable metrics and long battery life without bulk. The standout reason to choose it is the combination of multi-band GPS and extended battery endurance, which together deliver accurate training data and long sessions between charges. The watch balances a slim, always-on color display with adaptive daily workouts and HRV-based morning reports, making it a practical choice for runners who track performance, recovery and sleep.

Key Features

• Slim full-color display: An always-on screen that is easy to read in direct sunlight while staying light on the wrist for long runs and daily wear.
• Long battery life: Up to 14 days in smartwatch mode and up to 30 hours in GPS mode so users can rely on it for extended training blocks and multi-day events.
• Adaptive daily workouts: Daily suggested workouts that update after every run to match current performance and recovery, helping athletes stay on plan.
• Morning report with HRV status: Summarizes sleep, HRV status and a daily workout suggestion to give quick insight into readiness and recovery each morning.
• Advanced race and training tools: Race widget, training status and completion time predictions based on course and weather help with race-day strategy.
• Running power and dynamics: When paired with optional pod or HRM-Pro, provides continuous running power and advanced metrics like stride length and ground contact time.

Who It's For

The Forerunner 255 is best for recreational and serious runners who want a lightweight watch that still delivers advanced training guidance, multi-band GPS accuracy and long battery life for frequent training and races. It also suits multisport athletes who appreciate more than 30 activity profiles including cycling and swimming.

Runners who need chest-strap level heart monitoring or those who expect seamless audio connectivity for earbuds may want to check compatibility and consider adding external sensors, since connectivity experiences reported by some users are mixed and chest straps are recommended for some advanced metrics.

Pros & Cons

Pros

• Excellent battery life that supports long GPS sessions and daily use without frequent charging.
• Accurate workout tracking and adaptive daily suggested workouts that respond to performance.
• Comprehensive recovery and wellness insights, including morning report and HRV status for better planning.
• Lightweight, slim design with an always-on, sunlight-readable color display for comfort and visibility.

Cons

• Connectivity to wireless earbuds can be inconsistent for some users, producing mixed results.
• Some advanced metrics require external accessories such as a Running Dynamics Pod or HRM-Pro to get full capability.

Specifications

Our Verdict

The Forerunner 255 is a strong choice for runners who want accurate tracking, adaptive training guidance and industry-leading battery life in a slim package. It represents good value for athletes seeking a dependable daily trainer with useful recovery insights, provided they understand that a few advanced features perform best with optional external sensors.

Frequently Asked Questions

How long does the battery last?
Up to 14 days in smartwatch mode and up to 30 hours in GPS mode depending on settings and usage.

Does it give training suggestions?
Yes, it provides daily suggested workouts that adapt after every run and offers training status and race predictions.

Do I need extra sensors for running power?
Running power and advanced dynamics require a Running Dynamics Pod or HRM-Pro monitor, which are sold separately.