App Icon

Half Marathon Race Predictor


UPDATE: I have updated the prediction algorithm to hopefully be more accurate and a little less jumpy when going up hills or slowing down at water stations. It will use different factors to predict your finish time depending on where you are at in the race. Please let me know if you have see any issues.</p><p></p><p>Predicts your estimated half marathon finish time while you are running the race. No longer do you need to manually calculate your finish you will know 30 seconds into your race if you are on pace to crush your old PR or not. </p>


updated supported watches


  • Captain Marvel Captain Marvel
  • D2™ Air D2™ Air
  • D2™ Bravo D2™ Bravo
  • D2™ Bravo Titanium D2™ Bravo Titanium
  • D2™ Charlie D2™ Charlie
  • D2™ Delta D2™ Delta
  • D2™ Delta PX D2™ Delta PX
  • D2™ Delta S D2™ Delta S
  • Darth Vader™ Darth Vader™
  • Descent™ Mk1 Descent™ Mk1
  • Descent™ MK2 Descent™ MK2, Descent™MK2i
  • Descent™ Mk2S Descent™ Mk2S
  • First Avenger First Avenger
  • ForeAthlete® 735XTJ ForeAthlete® 735XTJ
  • Forerunner® 230 Forerunner® 230
  • Forerunner® 235 Forerunner® 235
  • Forerunner® 245 Forerunner® 245
  • Forerunner® 245 Music Forerunner® 245 Music
  • Forerunner® 630 Forerunner® 630
  • Forerunner® 645 Forerunner® 645
  • Forerunner® 645 Music Forerunner® 645 Music
  • Forerunner® 735XT Forerunner® 735XT
  • Forerunner® 745 Forerunner® 745
  • Forerunner® 920XT Forerunner® 920XT
  • Forerunner® 935 Forerunner® 935
  • Forerunner® 945 Forerunner® 945
  • Forerunner® 945 LTE Forerunner® 945 LTE
  • fēnix® 3 fēnix® 3, quatix® 3, tactix® Bravo
  • fēnix® 3 HR fēnix® 3 HR
  • fēnix® 5 fēnix® 5, quatix® 5
  • fēnix® 5 Plus fēnix® 5 Plus
  • fēnix® 5S fēnix® 5S
  • fēnix® 5S Plus fēnix® 5S Plus
  • fēnix® 5X fēnix® 5X, tactix® Charlie
  • fēnix® 5X Plus fēnix® 5X Plus
  • fēnix® 6 fēnix® 6
  • fēnix® 6 Pro fēnix® 6 Pro, fēnix® 6 Sapphire
  • fēnix® 6 Pro Dual Power fēnix® 6 Pro Dual Power
  • fēnix® 6 Pro Solar fēnix® 6 Pro Solar
  • fēnix® 6 Solar fēnix® 6 Solar
  • fēnix® 6S fēnix® 6S
  • fēnix® 6S Dual Power fēnix® 6S Dual Power
  • fēnix® 6S Pro fēnix® 6S Pro, fēnix® 6S Sapphire
  • fēnix® 6S Pro Dual Power fēnix® 6S Pro Dual Power
  • fēnix® 6S Pro Solar fēnix® 6S Pro Solar
  • fēnix® 6S Solar fēnix® 6S Solar
  • fēnix® 6X Pro fēnix® 6X Pro, fēnix® 6X Sapphire, fēnix® 6X Pro Solar, tactix® Delta Sapphire, quatix® 6X Solar, tactix® Delta Solar, tactix® Delta Solar Ballisitcs
  • fēnix® Chronos fēnix® Chronos
  • MARQ™ Adventurer MARQ™ Adventurer
  • MARQ™ Athlete MARQ™ Athlete
  • MARQ™ Aviator MARQ™ Aviator
  • MARQ™ Captain MARQ™ Captain, MARQ™ Captain: American Magic Edition
  • MARQ™ Commander MARQ™ Commander
  • MARQ™ Driver MARQ™ Driver
  • MARQ™ Expedition MARQ™ Expedition
  • MARQ™ Golfer MARQ™ Golfer
  • Mercedes-Benz Venu® Mercedes-Benz Venu®
  • quatix® 6 quatix® 6
  • quatix® 6X quatix® 6X, quatix® 6X Solar, quatix® 6X Dual Power
  • Rey™ Rey™
  • Venu® Venu®
  • vívoactive® vívoactive®
  • vívoactive® 3 vívoactive® 3
  • vívoactive® 3 Mercedes-Benz® Collection vívoactive® 3 Mercedes-Benz® Collection
  • vívoactive® 3 Music vívoactive® 3 Music
  • vívoactive® 4 vívoactive® 4, GarminActive
  • vívoactive® 4S vívoactive® 4S, GarminActive S
  • vívoactive® HR vívoactive® HR
平均評価: (29評価)

2021/04/03 | バージョン3.0.0

Very accurate. Used it today for the first time time in my long run training. At 6,9km it predicted 2:22:46 and the end result turned out to be 2:23:22, but I could for sure have gone a bit faster in the end if it had bern a race. The predicted time went up 10-20 min the three times when I walked a bit to drink and refill energy, but it came back to a good prediction again only 30 sec after I started running again.

2018/11/30 | バージョン2.1.0-upd5

you can use Training mode on 235 for this

Ricky McLeary
2018/10/15 | バージョン2.1.0-upd5

Absolutely spot on, highly recommend this.

2018/02/06 | バージョン2.1.0-upd5

I loved this data field on my Vivoactive. I just bought the Vivoactive 3 and I am very sad it is not compatible for Vivoactive 3...

2017/04/02 | バージョン2.1.0-upd5

Top for Forerunner 235

2016/05/11 | バージョン2.1.0-upd1

Installé sur Forerunner 235. Impossible d'ajouter l'information dans les écrans de données. Non repéré par ma montre. dommage...

2016/05/11 | バージョン2.1.0-upd1

Used it last Sunday on a race and it was SPOT ON. Maybe it could be in KM or just say HM for us non milers . Would love to see the SMART Predictor on the 235 as well. Anyways great field and Thank You for your efforts.

Felix Schumpelick
2016/02/22 | バージョン2.1.0-upd

Thanks so much ! Works great on fenix 3 6.80 :)

2016/01/22 | バージョン2.1.0

I have not used the app yet. To see this data one must add it to your data screen.

2016/01/06 | バージョン2.1.0

E descargado la aplicacion en mi Fenix 3 y no aparece por ningun sitio no puedo ejecutarla porque no la veo en el Fenix 3

2015/12/09 | バージョン2.1.0

Downloaded on vivoactive. Can't find anywhere on the watch. Help is appreciated. Thanks.

Андрей Заботин
2015/10/25 | バージョン2.0.0-upd

I just tried it yesterday on half-marathon. Very conveniently and works great! Thanks! Попробовал вчера на полумарафоне. Удобно и работает отлично.

2015/10/15 | バージョン2.0.0-upd

Can't seem to find this on my Fenix 3. I've downloaded the app but it's nowhere to be seen on the watch. It's not under my running fields and it's not shown as a stand alone app. Can you please advise me..

2015/09/23 | バージョン2.0.0-upd

Not appearing on my vivoactive screen!

2015/08/25 | バージョン2.0.0-upd

I love this data field. It is usually spot on and great for seeing how a training pace would play out for a half. Can't recommend this product enough and think it should be a standard data field

Paul Jones
2015/06/14 | バージョン2.0.0

Really accurate and incredibly useful !

Matthew P. Barnson
2015/05/18 | バージョン2.0.0

Does exactly what it says. Helped me nail my half marathon planned pace within a few seconds per mile. This is a great tool for anyone looking for exact pacing in a half marathon!

Jason Peters
2015/04/26 | バージョン2.0.0

Used it for the first time and it was pretty accurate.

Beth Olmstead
2015/04/26 | バージョン2.0.0

Help! I'm not finding it on my vivoactive to add it to my fields during an activity.

2015/04/25 | バージョン2.0.0

Very useful many thanks

Ada Gudex
2015/04/21 | バージョン2.0.0

Awesome app! It helped keep me on target for my half marathon race pace... Becomes more and more accurate as you settle into the race. Thanks for building this app!!!

Nick Pompei
2015/04/13 | バージョン1.1.3

Just used this yesterday for my first half of the year - worked flawlessly! Such a cool app and the fact that it can just be added right into a date field is perfect. Couldn't have asked for anything better, such a great app! Oh, helped me PR - 1:25:46 - thanks!

Brian Tolley
2015/04/11 | バージョン1.1.3

This worked awesome on my vivoactive during my half marathon. I impressed a few fellow runners when I told them our predicted total time.

2015/04/08 | バージョン1.1.3

Worked flawlessly at a recent half marathon.

2015/02/21 | バージョン1.1.3

Can you pls do this for km as well