For running watches, choose Forerunner 165 if you want a bright AMOLED and easy pace tools; pick Forerunner 255 for multisport, dual‑band GPS, and longer battery.
Garmin Forerunner 165
Garmin Forerunner 255
Best Budget Runner
- Bright AMOLED with touch + buttons
- HRV status & Morning Report
- Open‑water swim included
Forerunner 165
Balanced Training & Races
- Triathlon/multisport race mode
- Dual‑band GPS for tough routes
- Barometer‑based climb metrics
Forerunner 255
Music On The Wrist
- Offline playlists for phone‑free runs
- Pairs with Bluetooth headphones
- Same run metrics as the base model
Forerunner 255 Music
Running wearables shape how you pace, recover, and line up on race day. One leans into a rich AMOLED screen and simple training cues; the other stacks triathlon modes and stronger GPS. This guide gives you the quick verdict and the trade‑offs that nudge a buyer one way or the other.
In A Nutshell
The Forerunner 165 is the easy pick for runners who want a bright display, wrist‑based running power, and smooth daily coaching without extra complexity. The Forerunner 255 is the safer bet for brick workouts, open‑water plus bike plus run in one file, and dual‑band GPS for city streets or deep canyons. If you care most about screen clarity and comfort, lean 165. If you race tri or chase long GPS time, lean 255.
Side‑By‑Side Specs
Garmin Forerunner 165 — What We Like / What We Don’t Like
✅ What We Like
- Bright 1.2″ AMOLED with touch and buttons—easy to read at any pace.
- Wrist‑based running power and form metrics without extra pods.
- Light 43 mm case sits well for all‑day wear and sleep tracking.
⚠️ What We Don’t Like
- No triathlon/multisport file—swim, bike, and run must be saved separately.
- No pairing to bike power meters; cyclists will miss watt data.
Garmin Forerunner 255 — What We Like / What We Don’t Like
✅ What We Like
- Triathlon and Multisport modes save the whole race with transitions.
- Dual‑band GNSS tracks clean lines in cities, woods, and mountains.
- Pairs with cycling power sensors and more accessories.
⚠️ What We Don’t Like
- Transflective screen is power‑lean but less punchy indoors.
- List price sits higher; the Music variant adds another $50.
Forerunner 165 Or 255: Which Fits You Better
Performance & Speed
For tracking pace and distance, both lock satellites fast and log steady splits. The difference shows up in tougher spots. The 255 adds dual‑band positioning (L1+L5), which holds a line near tall buildings or on tight switchbacks. The 165 uses multi‑GNSS without the second frequency, which is fine for parks and road loops, but the 255 handles tricky terrain with less drift.
Race day flow also diverges. The 255 has a full triathlon mode that records swim‑to‑bike‑to‑run with transitions in one file. The 165 can record pool and open‑water swims, plus bike and run, but each saves as a separate activity. If you do bricks or full tri, the 255 keeps life simple.
Display & Build
The 165’s 1.2″ AMOLED brings crisp text, bold charts, and smooth touch. If you view splits in low light or check sleep on the nightstand, it shines. The 255’s transflective MIP trades punch for endurance; it stays legible under midday sun and sips power during long efforts. Cases differ too: the 165 comes in a compact 43 mm; the 255 offers 46 mm or a smaller 41 mm (255S) for narrow wrists.
Battery & Charging
If you want the longest time between charges, the 255 wins. Expect up to 14 days as a watch and up to 30 hours of single‑band GPS logging. The 165 lands at up to 11 days and up to 19 hours of GPS. With screen always‑on and music, both drain faster, but the 255 holds an edge for ultra training weeks or back‑to‑back race weekends.
Cameras & Sensors
Both include wrist heart rate, SpO₂, a barometric altimeter for floors and climbs, and a compass. The 165 adds wrist‑based running power and form metrics right from the watch—no pod required. The 255 also reads running power (with accessories) and, more broadly, pairs to cycling power meters, making it a stronger pick for structured bike sessions.
Software & Updates
Daily Suggested Workouts and adaptive plans appear on both, along with Morning Report and HRV status. The 255 layers in Training Status and Load to gauge trending fitness from VO₂ Max, HRV, and recent effort. If you like seeing “Productive,” “Maintaining,” or “Peaking” based on your last weeks, that tilt goes to the 255. You can read Garmin’s write‑up in the Training Status section.
Swim features are strong on both. The 165 includes pool and open‑water profiles; the 255 adds triathlon/multisport to chain events. For a feel of the open‑water workflow, see Garmin’s Open‑Water swim steps.
ℹ️ Good To Know: The 165 records open‑water as a single‑sport swim and the 255 records full tri events with transitions. If you care about one tidy file for race day, the 255 saves time later.
Ports & Connectivity
Both pair to common sensors over ANT+ and Bluetooth. The 165 links with chest straps, foot pods, and bike speed/cadence sensors, plus Bluetooth headphones on the Music model. The 255 adds pairing with bike power meters and broader accessory options for cyclists. Garmin Pay works on both for quick checkout after a run.
Pricing & Packages
At list price, the 165 starts at $249.99, with a $299.99 Music variant. The 255 launched higher at $349.99, with a $399.99 Music variant. Street pricing moves with promos, but the pattern holds: the 165 undercuts on price and screen polish; the 255 earns its keep with multisport and dual‑band GNSS. If you only run, the 165 covers the job. If you split time between pool, bike, and run, the 255 is the stress‑free route.
Price, Value & Ownership
Those gaps shape long‑term ownership. If your weeks lean run‑only, the 165’s AMOLED and comfort keep you smiling. If your calendar alternates pool, bike, and run blocks—or you chase routes that bend through dense downtowns—the 255 pays back in cleaner maps and one‑file race records.
Where Each One Wins
🏆 Multisport File — Forerunner 255
🏆 Dual‑Band GNSS — Forerunner 255
🏆 All‑Day Comfort — Forerunner 165
🏆 Bike Power & Sensors — Forerunner 255
Decision Guide
✅ Choose Forerunner 165 If…
- You want a bright, phone‑like screen that’s easy on the eyes indoors and at dusk.
- Your weeks are mostly runs, with an occasional swim or ride logged on its own.
- You value wrist‑based running power and simple guidance more than deep training analytics.
✅ Choose Forerunner 255 If…
- You race triathlon or do bricks and want one file with transitions.
- You train near tall buildings or on steep trails and want dual‑band GNSS to hold the line.
- You ride with a power meter and want watt data and broader accessory pairing.
Best Fit For Most Runners
If your training is run‑first, the Forerunner 165 is the pleasant daily pick. The screen is crisp, the case is light, and wrist power plus HRV‑driven guidance keeps you on track. If your calendar has swim‑bike‑run blocks or you crave cleaner tracks in tough signal areas, the Forerunner 255 makes the smarter buy. Either way you’re getting a capable tool; the right choice simply matches how you train.
Method: This guide compiles specs and pricing from Garmin’s US product pages and official manuals. Two quick references worth saving: Garmin’s Training Status overview and the 255’s Open‑Water swim steps.