The Forerunner 170 is an entry running watch for people who want to track everything from daily runs to races with 1 watch. The deciding points are 41g, about 20 hours in GPS mode, Suica and a barometric altimeter. Released May 28, 2026, JPY 47,800, a 1.2-inch OLED screen.
The Shoe Nerd's top pick
The Forerunner 170 is a watch where you pay JPY 8,000 for Suica and an altimeter. On battery alone, the Forerunner 70, JPY 8,000 cheaper, is 3 hours longer. Only the 170 has Garmin Pay (Suica), a barometric altimeter, an electronic compass and a gyro. For people who run hilly courses and who do not want to take out a wallet on the way home from a run, that JPY 8,000 has a reason. If it is flat roads only, I would choose the 70.
Key points
- From the previous Forerunner 165, the price goes JPY 39,800 → JPY 47,800, up about 2 tenths, and GPS-mode battery goes about 19 hours → about 20 hours
- On the multi-GNSS setting, about 14 hours. 3 hours shorter than the previous 165's about 17 hours
- Holds 3 full marathons. Falls over 5 hours short of a 100km trail
Is the Forerunner 170 worth buying: the cheaper 70 has a longer battery
The Forerunner 170 is a buy for people who enter full marathons and halves and also run hilly courses. At 41g and about 20 hours in GPS mode, the JPY 8,000 gap from the 70 is the price of Suica and a barometric altimeter.
The JPY 39,800 Forerunner 70 is about 23 hours, 3 hours longer than the 170 (23 − 20). How to compare entry-level watches is in the article on 12 running watches, so here I talk only about the 170.
Forerunner 170 weight and battery? The official numbers
| Item | Forerunner 170 |
|---|---|
| Release date | May 28, 2026 (pre-orders from May 21) |
| Official price | JPY 47,800 (the 170 Music is JPY 55,800) |
| Weight | 41g |
| Dimensions | 42.6 × 42.6 × 11.9mm |
| Screen type and size | OLED (AMOLED), 1.2 inches, 390 x 390 pixels |
| Battery with GPS on | GPS mode about 20 hours / multi-GNSS about 14 hours |
| Everyday battery | About 10 days (about 19 days in battery saver) |
| Water resistance | 5ATM (50m water resistant) |
| Maps | None (showing maps on the watch is not supported) |
| Dual-frequency GPS | Not supported |
| Colors | 2 colors for the 170, 4 colors for the 170 Music |
Divide the price by GPS-mode hours and it is JPY 2,390 per 1 hour (47,800 ÷ 20). Divide by the multi-GNSS setting and it is about JPY 3,414 (47,800 ÷ 14).
Multi-GNSS is a setting that receives not just the US GPS but other countries' satellites at once. Because it receives more signals, the battery is 6 hours, 30%, shorter (6 ÷ 20). It is a setting for days you want stable position between buildings or under trees, so if you plan to use it in a race, read the 14-hour figure.
Image: Rakuten Ichiba
Garmin Forerunner 170
Lowest price on Rakuten is JPY 43,350 (as of 10/13), ranging up to JPY 55,800 depending on the shop. Prices change daily.
RecommendedSee it on Super Sports XEBIOSee it on Rakuten IchibaSee it on Yahoo! Shopping JapanForerunner 170 vs 165: what changed from the previous model
The previous model is the Forerunner 165. The Japan official product page now carries a "discontinued" label. I lined up the numbers left on the page with the 170's numbers.
| Item | 165 | 170 | Difference |
|---|---|---|---|
| Official price | From JPY 39,800 | JPY 47,800 | +JPY 8,000 |
| Weight | 39g | 41g | +2g |
| Thickness | 11.6mm | 11.9mm | +0.3mm |
| GPS mode | About 19 hours | About 20 hours | +1 hour |
| Multi-GNSS | About 17 hours | About 14 hours | −3 hours |
| Everyday battery | About 11 days | About 10 days | −1 day |
| Display | 1.2 inches, 390 x 390 | 1.2 inches, 390 x 390 | Same |
| Price per hour of GPS | JPY 2,095 | JPY 2,390 | +JPY 295 |
The price rose about 20% (8,000 ÷ 39,800). GPS-mode battery grew 1 hour, about 5% (1 ÷ 19). Screen size and sharpness are the same numbers. On the spec table, it is a generation change that moved less than the price.
What stands out is the multi-GNSS row. The 165's about 17 hours is about 14 hours on the 170. 3 hours, about 18%, shorter (3 ÷ 17). The newer model has a shorter time on the heavy setting.
So what was added? The announcement lists 3 new features.
- Beginner Garmin Coach / recommended workouts: offers content that keeps intensity and volume down, or mixes running and walking
- Quick workouts: pick 2 or 3 items and it builds the interval content automatically
- Evening report: in addition to the morning report, shows the sleep time you need tonight and tomorrow's plan in the evening
All of these are about guidance inside the watch. There is no explanation comparing them with the 165. So I cannot say flatly "what the 165 lacks and the 170 has." What can be said in numbers stops at the differences in the table above.
The 70 now sits in the 165's price seat
The 165 is from JPY 39,800 and the 70 from JPY 39,800. The same amount. But the contents are not the same.
The 165's product page sensor field lists a barometric altimeter and compass. The announcement also writes that the electronic compass and barometric altimeter are "170 series only."
In other words, someone who used the 165 and switches to the 70 for the same amount loses the altimeter. To keep the altimeter, add JPY 8,000 for the 170. The staircase of entry-level prices has shifted up by 1 step.
Image: Rakuten Ichiba
Garmin Forerunner 165 (previous model)
Lowest price on Rakuten is JPY 39,800 (as of 10/13), ranging up to JPY 74,800 depending on the shop. Prices change daily.
RecommendedSee it on Rakuten IchibaSee it on Yahoo! Shopping JapanForerunner 70, 170 Music and 570 compared
Scroll the table sideways →
| 70 | 170 | 170 Music | 570 (47mm) | |
|---|---|---|---|---|
| Official price | JPY 39,800 | JPY 47,800 | JPY 55,800 | JPY 74,800 |
| Weight | 40g | 41g | 41g | 50g |
| GPS mode | About 23 hours | About 20 hours | About 20 hours | About 18 hours |
| Heavy setting | About 16 hours | About 14 hours | About 14 hours | About 14 hours |
| Music | None | None | Yes (about 6.5 hours) | Yes |
Difference from the 70: JPY 8,000 cheaper, 1g lighter, and a battery 3 hours longer. What the 170 has is Garmin Pay (Suica compatible), a barometric altimeter, an electronic compass and a gyro. The product page says the 70's built-in memory is 512MB and the 170's is 4GB.
Difference from the 170 Music: The gap is JPY 8,000 (55,800 − 47,800). You can put music on the watch and listen without a smartphone. Wi-Fi is only on this one too. Using GPS while playing music, the battery is about 6.5 hours. In a 6-hour full marathon, only 30 minutes remain (6.5 − 6).
Difference from the 570: The gap is JPY 27,000 (74,800 − 47,800). It adds dual-frequency GPS and a larger 1.4-inch screen. GPS-mode battery is 2 hours shorter on the 570 (20 − 18). The 570 does not show maps on the watch either.
- Flat roads only. Choose by battery and price → 70
- Run hills and mountains too. Want to handle ticket gates and shopping with the watch → 170
- Listen to music without carrying a smartphone → 170 Music (if you play music nonstop in a full marathon, the battery has 30 minutes to spare)
- Want to reduce position drift even between buildings → 570
Image: Rakuten Ichiba
Garmin Forerunner 70
Lowest price on Rakuten is JPY 36,099 (as of 10/13), ranging up to JPY 39,800 depending on the shop. Prices change daily.
RecommendedSee it on Rakuten IchibaSee it on Yahoo! Shopping JapanWhat I like
At 41g, an entry-level watch has an altimeter. A barometric altimeter is a part that measures height climbed from changes in air pressure. It picks up fine ups and downs better than getting height from GPS alone. For people who want to see "how many meters I climbed" on a hilly course, it is the most meaningful part in the price gap from the 70.
You can come home without a wallet. Garmin Pay supports Suica. Buy a drink where you run, then take the train home. For those scenes, the watch alone is enough.
The screen is the same OLED as the higher models. 1.2 inches, 390 x 390 pixels. It did not downgrade the screen type because it is an entry model. It works by both touch and buttons, and touch can be turned off.
Though an entry model, it has race-oriented items lined up. The product page list includes race predicted time, PacePro that gives target pace per segment, course navigation, running power and training readiness. The activities also include trail running, track running, ultra running and open water swimming.
Things to watch
The battery is not on the long side among siblings. It is 3 hours shorter than the 70, and 3 hours shorter on the heavy setting than the previous 165. There is no case in the numbers for choosing the 170 for battery.
No map shows on the watch. Course navigation is on the list, but map display is not supported. It is guidance following a line, and you cannot see the roads or terrain around you. Someone who wants to see a map on an unfamiliar mountain path is on the side of the SUUNTO Run 2, which holds maps.
Dual-frequency GPS is not supported. The setting that receives 2 frequencies starts from the 570 and up.
Music only on the Music model. You cannot add the music function to the 170 later. It is something to decide before buying.
Is the Forerunner 170 battery enough for races? Who does it fit?
Divide the battery hours by the race time limit. If over 1, it is enough. The time limits are numbers I read from official entry guides in this site's race calendar and the mandatory gear article.
| Racing | Cutoff | GPS mode (20 hours) | Multi-GNSS (14 hours) |
|---|---|---|---|
| Marathon | 6 hours | Enough (3.3 races' worth) | Enough (2.3 races' worth) |
| Middle-distance triathlon (Nagara River 102km) | 7 hours 30 minutes | Enough | Enough |
| Long triathlon (Miyakojima) | 13 hours | Enough | Enough (1 hour to spare) |
| Izu Trail Journey 70k | 14 hours | Enough | Just enough |
| OSJ KAMI100 100K | 25 hours | 5 hours short | 11 h short |
| Tokyo100 (101km) | 30 hours | 10 hours short | 16 hours short |
Full marathon: enough. Two or more races' worth on either setting. In other words, you have the freedom to choose the setting.
100km trail: not enough. In a race with a 25-hour limit, it falls 5 hours short even in GPS mode (25 − 20). As someone who enters trails too, I read the 20-hour figure as "up to just before a 70km-class mountain." With 14 hours for Izu, 6 hours remain, and races over 21 hours are out.
Triathlon: the battery is enough. Even a long race with 13 hours, GPS mode leaves 7 hours (20 − 13).
- Good fit: Someone who enters full marathons and halves. Someone who runs hilly courses. Someone who wants Suica on their watch.
For trails over 70km or maps on the watch, there are other ways to choose. If you have no complaint about the 165's battery, wearing it out first is in time. If it is flat roads only and you use neither Suica nor the altimeter, the 70 is enough.
Price and where to buy
| Model | Official price | Rakuten price range |
|---|---|---|
| Forerunner 170 / 170 Music | JPY 47,800 / JPY 55,800 | JPY 43,350–55,800 |
| Forerunner 165 (previous model, discontinued) | From JPY 39,800 | JPY 39,800–74,800 |
| Forerunner 70 | JPY 39,800 | JPY 36,099–39,800 |
| Forerunner 570 | JPY 74,800 | JPY 67,320–74,800 |
What to decide before buying is whether you need music. The 170 and 170 Music have separate product numbers and different color counts: 2 colors for the 170, 4 for the Music. Choose by color and pick the Music model, and the price gap in the table gets added.
A 165 remaining in stores has a reason to be chosen if sold cheaply as the previous model. GPS mode differs by 1 hour, and on the heavy setting it is actually 3 hours longer. What it lacks are the 3 new guidance functions in the announcement.
Image: Rakuten Ichiba
Garmin Forerunner 170
Lowest price on Rakuten is JPY 43,350 (as of 10/13), ranging up to JPY 55,800 depending on the shop. Prices change daily.
RecommendedSee it on Super Sports XEBIOSee it on Rakuten IchibaSee it on Yahoo! Shopping Japan
Image: Rakuten Ichiba
Garmin Forerunner 570
Lowest price on Rakuten is JPY 67,320 (as of 10/13), ranging up to JPY 74,800 depending on the shop. Prices change daily.
RecommendedSee it on Rakuten IchibaSee it on Yahoo! Shopping JapanFAQ
How do the Forerunner 170 and 165 differ? Is it worth upgrading?
From the battery numbers, no. GPS mode grew by only 1 hour, and multi-GNSS got 3 hours shorter. The reasons to upgrade are if you want to use the 3 things in the announcement: the beginner coach, quick workouts and the evening report.
Can the Forerunner 170 show maps?
No. On the product page, showing maps on the watch is not supported. Course navigation is on the list, so the use is following a route loaded in advance. For people who want maps too, the article on 12 watches lines up watches with maps.
How do the Forerunner 170 and 70 differ? Does Suica work on the 70?
Suica does not work on the 70. The announcement says Garmin Pay (Suica compatible) and the barometric altimeter are "170 series only." Of the JPY 8,000 gap from the 70, this is the function you also use on days you do not run.
