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Best watch for marathon training
Opens Amazon.com · Prices change often
Garmin Forerunner 570 – 47mmThe same race for one price band lessUnder $600
COROS PACE 4Best marathon watch on a budgetUnder $250
Garmin Forerunner 70Best Garmin coaching under $250Under $250Price bands, not prices
| Watch | Verdict | Who it suits | The catch | Price band and link |
|---|---|---|---|---|
 Garmin Forerunner 970Our pick | Best watch for marathon training | Serious road runners who want race-accurate GPS, multi-band battery that projects to about Garmin's 21 hours, and Garmin's deepest training tools | Some units register phantom touchscreen taps, and a warranty swap has cured it for some owners but not all | Under $800View on Amazon (opens in a new tab) |
| Garmin Forerunner 570 – 47mmBuy | The same race for one price band less | Road marathoners on familiar routes who never need a map and don't mind charging twice a week with the screen always on | Three to four days between charges with the always-on screen | Under $600View on Amazon (opens in a new tab) |
| COROS PACE 4Buy | Best marathon watch on a budget | Runners who want the most race-day battery and top-tier GPS for the least money, and will judge their own recovery | No readiness score, and the on-watch training load resets every Monday | Under $250View on Amazon (opens in a new tab) |
| Garmin Forerunner 70Buy | Best Garmin coaching under $250 | First-time marathoners who want Garmin Coach plans and a readiness score on the wrist | It doesn't predict your race time | Under $250View on Amazon (opens in a new tab) |
| COROS PACE 4 ProWait | New: wait for the battery fix | Runners who want a big, bright screen and maps for less than a Forerunner 570 | Multi-band battery tested well under COROS's claim, with the promised fix not yet released | Under $450 |
Every watch we'd strap to a marathoner's wrist will still be recording at the finish, even on a 6:00 day. Battery stopped being the race-day question a while ago. Now it's the Wednesday-night question of whether you remembered to charge. What's left to decide is GPS you can trust over 26.2, and training tools worth listening to for a whole block. Milewright's pick for marathon training is the Garmin Forerunner 970. Garmin's manual promises 21 hours of multi-band GPS. A measured 10K race, screen always on, drained it at a rate that projects to almost exactly that. The same race had it finishing a whisker short of the course. Its Running Tolerance score is the training number long-term testers credit with getting them through a mileage build in one piece. The catch: some units register taps nobody made, and a warranty swap has fixed that for some owners but not all.
Garmin Forerunner 970Under $800Opens Amazon.com · Prices change often
Three things, and battery isn't one of them.
First, maps and a flashlight. Drop those, along with Running Tolerance and sapphire glass, and the Forerunner 570 runs the same race for one price band less. Our Forerunner 570 vs 970 comparison goes mode by mode. Second, money. The COROS PACE 4 carries more race-day battery than either Garmin and tracks as well for under $250. Its training brain is thinner. Third, Garmin's coaching on a small budget, which is the Forerunner 70's job.
On an iPhone and eyeing the Apple Watch Ultra 4? Read our Apple Watch vs Garmin for running comparison first. It only works with an iPhone, and every marathon it has been tested on so far read long. If your longest day runs well past a marathon, the GPS battery planner works out which watch lasts it.
Price band: under $800
Garmin prints 21 hours of multi-band GPS. Nobody has run a 970 down in that mode, but a 10K race drain projects to about 21 hours. Burning 4.8%/hour in that race with the screen always on, it uses about a seventh of the charge over a 3:00 marathon. A 6:00 one takes a little under a third. You'll start the race worrying about your hamstring, not your watch.
It's accurate where it counts. Across about 30 workouts against reference GPS units, its land tracks came out perfect or near perfect. On that measured 10K it came in about two bus lengths short. Hold an even pace and its optical sensor reads like a chest strap, which is about the ceiling for wrist heart rate.
The training tools are why it beats the cheaper watches. Training Readiness tells you whether today's tempo run is a good idea. The race predictor and PacePro plan race day itself. Running Tolerance, which the 570 lacks, watches how fast you're piling on mileage. Two testers who wore the 970 for six months or more credit it with getting them through a build without injury. That's where most marathons are won or lost, months before the start.
Between charges, it lasts four to five days with the screen always on below maximum brightness. Owners who don't say which display setting they use report about two weeks between charges. The maps and LED flashlight earn their keep on a 5 a.m. long run in a strange city.
Where it falls down is the screen itself. On Garmin's own 970 forum, the busiest unresolved complaint is ghost touches: a scroll lands as a tap, and menus open by themselves. It seems to vary watch by watch, and Garmin deals with each case as it comes. A replacement has fixed it for some owners and not for others, and one went through three. It's an irritation with a warranty route, not a fault that will cost you a race. We'd buy it.
Garmin Forerunner 970Under $800Opens Amazon.com · Prices change often
Price band: under $600
On race morning a Forerunner 570 is most of a 970. You get Training Readiness, the race predictor, projected race time and PacePro. Spotify, Amazon Music, Deezer and YouTube Music download to it; Apple Music doesn't. You give up maps, the LED flashlight, sapphire glass, Running Tolerance and a third of the multi-band battery on paper.
That paper is still plenty. Garmin claims 14 hours in multi-band on the 47mm. In the same 10K race test, a 570 of unrecorded size, possibly the smaller-cased sibling rather than this 47mm, burned 6.0%/hour with the screen always on, a drain that projects past the claim. It was also one short race. One sample on an unidentified part is not a sign-off in my book, so we plan on the 14 hours. Even then, a 6:00 marathon uses well under half the charge. Play music in multi-band and Garmin's manual cuts it to 8 hours. That's still a marathon with a playlist, with less to spare.
A 47mm logged about 150 miles beside chest straps and reference watches. Its tracks and heart rate never wandered meaningfully from them. It also beat the older Forerunner 265 on a twisting city half.
The catch is days between charges. With the screen always on, a 47mm needed charging every three to four days with daily runs. With raise-to-wake it lasted over a week. Garmin's 570 manual puts the cure in its battery tips: stop using the always-on screen and turn the brightness down. Twice-a-week charging is a habit, not a hardship. For a road runner who never navigates by map, we'd buy it and put the savings toward race entries.
Garmin Forerunner 570 – 47mmUnder $600Opens Amazon.com · Prices change often
Price band: under $250
The cheapest watch here has the most race-day battery of the three buys. COROS claims 31 hours in dual-frequency, or 24 with the screen always on. Measured in max GPS with always-on, it drained 4%/h, which projects to roughly COROS's own always-on figure. A 6:00 marathon takes about a quarter of the charge.
The GPS is no compromise either. Over six months that took in the London Marathon and the Paris Half, testers found its tracks matching the Forerunner 970's almost flawlessly. With the nylon band it comes to 1.1 oz (32 g), and a few miles in you'll stop noticing it's there. It comes with free marathon plans and race predictions, gained Pace Strategy in a March update, and asks for no subscription. Our PACE 4 review has the rest. COROS vs Garmin sets it beside the Garmins at each price.
The catch is the training brain. There's no readiness score, only an overnight HRV status. The training-load figure on the watch resets every Monday, so by your Sunday long run it describes a week that's nearly over. If you want the watch to judge your recovery, the Garmins do it better. If you'd rather judge it yourself and spend the difference on shoes, we'd buy it.
COROS PACE 4Under $250Opens Amazon.com · Prices change often
Price band: under $250
The Forerunner 70 skips multi-band GPS, and on the evidence it barely matters. Downtown among tall buildings, its tracks were virtually identical to what a fēnix 8 Pro recorded with multi-band switched on. Training Readiness and Garmin Coach's adaptive plans come on the wrist with no subscription.
Battery is the thinnest here. Its best GPS mode claims 16 hours, and one test hour in that mode burned just under 10%/hour. That leaves a bit under half after a 6:00 marathon. It's enough, with less spare than anything else on this page. According to DC Rainmaker, you can swap its battery yourself, which few watches allow.
The catch is that it won't predict your race time. For a first marathon where the goal is the finish line, that's a missing nicety. For a runner chasing a time, it's the reason to step up to the 570. For a first marathon on Garmin, we'd buy it.
Garmin Forerunner 70Under $250Opens Amazon.com · Prices change often
Price band: under $450
This is the September launch with the big 1.47 in screen, sapphire and a titanium bezel, at 1.5 oz (43 g) on nylon. COROS's battery page lists 40 hours in its multi-band Max mode on the default display. It drops to 30 hours when the screen stays lit. DC Rainmaker's runs in that same mode, display lit throughout, pointed to under 20 hours. One run of 90 minutes took 8% of the charge. COROS traced the shortfall to software bugs in the GPS system and in how it scans for cycling sensors, and says a fix will arrive in November. Its release notes on October 30 showed nothing newer than the September build. COROS deserves credit for admitting the bug in public, which beats the usual silence. But a promised fix isn't a measured one.
Race day isn't where this bites. Even under 20 hours, a 6:00 marathon leaves about two-thirds of the charge. The cost shows up between charges across a training block. The readiness score is missing here too, as on the PACE 4. Wait for the fixed firmware and a fresh battery test. If it lands near COROS's always-on figure, this becomes the most interesting COROS for a marathoner.
The Apple Watch Ultra 4 (September) claims 18 hours in a normal outdoor run. A tester's extrapolation from a ride and a longer activity projects to about 18.6 hours. Nobody has yet run one down in an outdoor run. Its 45-hour Max Extended mode gets there by hiding live splits and alerts, which is no use when you're pacing. The open question for a marathoner is distance. One marathon logged 26.57 mi, another finished more than half a mile long, and one owner's watch read nearly a mile over. It needs an iPhone. What we'd wait for is a race checked against the certified course line, not another watch on the other wrist. Until then, our Apple Watch vs Garmin comparison weighs it properly.
The base fēnix 9 47mm (also September) claims 25 hours of multi-band GPS. Nearly every test so far was on Pro models, so wait for one on the base watch. Under $1,000 is a lot of watch for running in a straight line, and nothing on record changes the answer here.
Each watch's box figures for battery and GPS went up against what reviewers and owners got from that precise model. We noted the screen mode and firmware behind every gap. Nothing could win without two separate kinds of proof on the very model sold, one of them independent of the maker. A result from a sibling or an unstated case size is labeled as such. Behind this page: 14 models weighed, with 10 maker manuals in that number; 367 sources kept in full across all of Milewright's research; and 148 Reddit threads read and summarized for you rather than kept whole. The CPSC recall database shows no recall naming Garmin, Apple Watch or COROS.
Yes, on every pick. The tightest is the Forerunner 70, which leaves a bit under half its charge after a 6:00 finish. The roomiest of the buys is the PACE 4, using about a quarter. The evidence section below breaks down every tested watch from 3:00 to 6:00. Watch the music line, though. Garmin's own multi-band figures with music drop sharply: 8 hours on the 570, 12 on the 970. If your race goes past a marathon, use the GPS battery planner.
Less than the marketing implies. Garmin's manual says multi-band helps "in challenging environments", meaning tall buildings and trees. On open roads, Garmin's single-band Forerunner 70 matched a multi-band flagship even downtown. If your marathon threads through skyscrapers, multi-band is cheap insurance. If not, the antenna matters more than the band count. Our most accurate GPS watch guide covers it.
Because you don't run the tangents the course measurer ran. Every wobble in the track adds a few phantom yards, so most watches read a touch long over 26.2. That's normal. It's also a reason to pace by feel late in the race rather than chase the watch's mile splits. For a clean start, Garmin's manual for the Forerunner 570 says to find open sky, tilt the screen upward and hold still until the satellites lock. It also says to sync before race day so the watch's satellite data is current.
No. COROS charges nothing. On Garmin, Connect+ is optional. The manual lists the paid extras: AI insights, LiveTrack+, Garmin Trails and nutrition logging. Garmin told DC Rainmaker that everything free before Connect+ stays free. Training Readiness and the race predictor aren't on that paid list.
| Watch | Buy | Best for | Multi-band battery: box vs tested | What a 6:00 marathon uses |
|---|---|---|---|---|
| Garmin Forerunner 970 | View on Amazon (opens in a new tab) | Best overall | 21 h claimed; a 10K race drain projects to about 21 h | A little under a third |
| Garmin Forerunner 570 (47mm) | View on Amazon (opens in a new tab) | Road racers who never need a map | 14 h claimed; one 10K drain projects past it, case size unstated | Well under half |
| COROS PACE 4 | View on Amazon (opens in a new tab) | The tightest budget | 31 h claimed (24 h always-on); 4%/h tested | About a quarter |
| Garmin Forerunner 70 | View on Amazon (opens in a new tab) | Garmin coaching under $250 | No multi-band; 16 h claimed in its best mode; just under 10%/hour tested | A bit over half |
| COROS PACE 4 Pro | Wait | Wait for the fix | 40 h claimed (30 h always-on); under 20 h projected | About a third |
Best watch for marathon training
The PACE 4 gives you more battery for less, and the 570 gives you the same race for less. Neither watches your training as closely, and the training is where a marathon is decided. The 970's GPS measured true on a race course, and its race drain projects to about the hours Garmin prints. Running Tolerance is the feature most worth paying for when the miles start stacking up. Charge it on Saturday, and the only thing left to worry about at the start line is you.
Garmin Forerunner 970Under $800Opens Amazon.com · Prices change often
Share of a full charge used at each finish time, worked out from the tested drain. Where a watch has no test in its multi-band mode, the row says which mode was measured.
| Watch | Box claim (multi-band) | Tested drain | 3:00 finish | 4:00 finish | 5:00 finish | 6:00 finish |
|---|---|---|---|---|---|---|
| Forerunner 970 | 21 h | 4.8%/hour (10K race, always-on) | About a seventh | About a fifth | About a quarter | Under a third |
| Forerunner 570 | 14 h (47mm) | 6.0%/hour (one 10K, always-on, on a 570 of unstated case size that may have been the smaller sibling) | Under a fifth | About a quarter | Just under a third | Over a third |
| COROS PACE 4 | 31 h (24 h always-on) | 4%/h (max GPS, always-on) | An eighth | A sixth | A fifth | A quarter |
| COROS PACE 4 Pro | 40 h (30 h always-on) | Under 20 h projected; 8% in a 90-minute run (max GPS, always-on) | A sixth | Over a fifth | Over a quarter | About a third |
| Forerunner 70 | No multi-band (16 h All-Systems) | Just under 10%/hour (best GPS mode, one hour) | Nearly a third | Nearly two-fifths | Nearly half | Nearly three-fifths |
| COROS APEX 4 (46mm) | 41 h | 2%/h (dual-frequency with navigation, long hike) | A sliver | Under a tenth | A tenth | An eighth |
| Apple Watch Ultra 4 | 18 h (standard workout) | 7%/hour (one trail run, normal workout mode) | A fifth | Over a quarter | Over a third | Over two-fifths |
| Suunto Run | 20 h | 19 h measured in Colorado; about 10%/hour in Alaskan cold | Nearly a third (cold) | Nearly two-fifths (cold) | Nearly half (cold) | Nearly three-fifths (cold) |
Notes on the table:
| Watch | Band | Multi-band claim | Race or GPS evidence | Here |
|---|---|---|---|---|
| Garmin Forerunner 970 | under $800 | 21 h | Finished a measured 10K a whisker short; near-perfect land tracks over about 30 workouts | Overall pick |
| Garmin Forerunner 570 (47mm) | under $600 | 14 h | 47mm: no meaningful error over about 150 miles; a 570 of unstated size finished the measured 10K a whisker long | Pick |
| COROS PACE 4 | under $250 | 31 h | Near flawless over six months, including a marathon and a half | Pick |
| Garmin Forerunner 70 | under $250 | None (16 h All-Systems) | Downtown tracks matched a multi-band fēnix 8 Pro | Pick |
| COROS PACE 4 Pro | under $450 | 40 h | Matched a fēnix 9 Pro on trails; one city loop offset to the wrong side of the street | Wait |
| Apple Watch Ultra 4 | under $800 | 18 h | Two marathons read long, one at 26.57 mi | New, listed with facts |
| Garmin fēnix 9 (47mm) | under $1,000 | 25 h | No test of the base model | New, listed with facts |
| COROS APEX 4 (46mm) | under $500 | 41 h | Good without a route loaded; over-smoothed with navigation on launch firmware | Considered |
| Polar Vantage M3 | under $500 | 27 h | Split: close to a fēnix 8 on runs, wobbly downtown | Considered |
| Suunto Run | under $200 | 20 h | 1.98 mi on a known 2-mile course | Considered |
| Garmin Instinct 3 (45mm AMOLED) | under $350 | 23 h | Accurate on a fixed course | Considered |
| Garmin vívoactive 6 | under $300 | None (17 h All-Systems) | Within a few hundredths of a mile on a 2-mile course | Considered |
| Garmin Forerunner 165 | under $200 | None (17 h All-Systems) | Strong single-band tracks, on an unstated edition | Considered |
| Garmin Forerunner 170 | None (14 h All-Systems) | Identical tracks to the Forerunner 70 | Considered |
How we research
Milewright doesn't test watches. It sets each maker's claim against what labs, reviewers and owners measured on the exact same model, and tells you which number to believe.
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