Garmin Forerunner 235 Review

garmin forerunner 235 next to garmin forerunner app on an iphone

Garmin Forerunner 235 Quick Ratings

Heart Rate Functions


Fitness/Sport Features


Ease of Use


Battery Life


Where To Get It

A Deep Dive Into The Garmin Forerunner 235 

If you have been seriously considering the Forerunner 230 then personally I’d add a few more ££’s and get the Garmin Forerunner 235 instead.

The convenience of built-in heart rate sensor in to the back of the watch means you are FREE from heart rate straps. Yes, it comes with a price increase, but personally, I think it is worth it. Identical features otherwise (with exception of battery life due to HR sensor battery usage).

This new FR235 follows on from the FR225 with some significant new features and differences between the two.

This review of the Garmin Forerunner 235 GPS runner’s watch has been written and researched by Tristan Haskins aka CardioCritic

  • Who Is It For?

  • Video Review

  • Pros

  • Cons

The Garmin Forerunner 235 is a technical GPS running watch with wrist based heart rate monitoring. As well as a very capable performance tracking sports watch it’s also a 24/7 activity tracker and sleep monitor.

The Forerunner 235 is for a dedicated / competitive runner looking to improve overall fitness and running performance.

If you are more of a casual jogger, park runner or just want to keep things simple then please consider the Garmin Forerunner 35 as a more user friendly runner’s watch with less technical functionality.

Confused by the Forerunner watch range? You’re not the only one with over a dozen models released in the last 10 years. To help you make the correct choice I’ve produced this guide to the Forerunner watches to help you get the latest and most appropriate model for your needs and budget.

Update June 2021 > Garmin have released the Garmin Forerunner 645 with internal music store, 24/7 Heart Rate, Stress Testing and more …

When we get our hands on a new GPS sports watch we like to test it as thoroughly as possible. Generally we produce one 10 – 12 minute video to give the potential owner a clear understanding of how the watch works, it’s key functions and features.

This is the first time we have ever produced 4 Videos ! They work so much better than words for some things, so we hope you find them useful.

The first video covers the FRONT end, the home page (Time of Day screen) and other screens accessed from scrolling down through the menus.

The second video covers the exercise screen views and data screens .. then there’s a video on Music Control then a final video on What is Connect IQ?

Video 1 – Time of Day & Activity Tracking

This is the FIRST of FOUR videos. As usual it’s unedited and is full of pauses, errrmms and other annoying habits. However, I don’t apologise for those and hope you get a good feel for the 235 from these videos.

This first one is 10 minutes long and gives a summary about all the key features and functions that can be accessed from the Time of Day screen by pressing the bottom left UP and DOWN buttons. This video covers:

  • Time of Day screen
  • Activity Tracker
  • Resting Heart Rate (RHR) graph views. 4 hour and 7 day summaries
  • Bluetooth connection
  • Do NOT disturb
  • Connect IQ Weather Forecasts
  • Connect IQ alternative clock face screens
  • Smartphone Notifications
  • and a short introduction to the Garmin Connect APP (iPhone or Android)

Video 2 – Exercise Mode – functions, features & settings

This video focuses on what you can see and do when in TRAINING MODE. Remember the Forerunner 235/230 has been aimed at the Runner.

It has 4 x sports profiles – RUN (GPS) – Indoor RUN (No GPS) – BIKE & OTHER. This video deals with the following functions and features all related to actual TRAINING:

  • DATA FIELDS (2 x customisable views of 1 – 4 fields)
  • Pre-programmed WORKOUTS
  • Setting up INTERVALS
  • RECOVERY timer – tells you when you will be fully recovered
  • VO2 Max score
  • FINISH TIME – real time 5k,10k,1/2M and Full Marathon predicted finish time based on realtime distance remaining and average pace
  • PREDICTED finish time calculator – the Forerunner gives a sensible estimation of your best 1M,5K,10K,1/2M and Full Marathon finish times
  • Smartphone Notifications

Some of the Best Features

In the gallery below I have added some screen captures of some of the very best features of the Garmin Forerunner 235. Remember, all these features are also available on the Forerunner 230 (assuming HR belt is used). In these images we have listed the following features, listing left to right and down

  • ALERTS – you can set PACE, DISTANCE, HEART RATE, CALORIES and TIME alerts. The watch will alert when you reach / exceed certain limits
  • FINISH TIME predictor. Before you go for a run, select a DISTANCE from 1M, 5K, 10K, Half Marathon and Full Marathon (or custom). Then go for your run. The top display of your Forerunner 235 will show you the DISTANCE REMAINING and the middle field shows PREDICTED FINISH TIME.
  • HISTORY – a summary of a training session
  • RECOVERY TIME – how long left until you are fully recovered. This is shown as a graphic and also represented numerically. Being fully recovered before a hard training session is very important. Understanding, appreciating and working with your level of recovery is a key to maintaining good health and fitness
  • RACE PREDICTOR – I really like this one, based on your current running sessions, the Forerunner 235 will give a predicted finish time for 5K, 10K, 1/2 Marathon and Marathon.
  • VO2 Max – following any running activity over 12 minutes, the Forerunner 235 will give a predicted VO2 Max score. From the tests I have undertaken, this is SPOT ON. It also agrees with the VO2 Max score I get from my Polar V800 – 52 to 53.
  • MUSIC CONTROLS – brilliant. Control your music tracks and volume as you train. I really like this when on my Turbo Trainer or Treadmill as my phone is on the other side of the room, plugged in to my AMP.
  • WEATHER WIDGET – this is one of the Connect-IQ widgets. Get the latest weather updates from your smartphone
  • SMARTPHONE NOTIFICATIONS – something Garmin have had in watches like the Vivoactive for some time. Receive incoming text, email, calendar and social media alerts on your watch.
  • TRAINING EFFECT – I was first introduced to Training Effect on the Suunto Ambit watches. Training Effect devised by FirstBeat Technologies will tell you how hard a session has actually been. A training effect of 2 to 3.5 is fine… no serious recovery required. Anything between 3.5 to 4 is HARD and you may take a couple of days to recover… 4 – 5 … take a few days off to recover 😉

Related Article: Forerunner 35 Review, an elite runner watch?

Related Article: Garmin 920xt Review is for anyone who runs!

Video 3 – Music Control

It took me a couple of weeks reviewing the 235 before I realised that it had the ability to control the music in my iPhone / Android phone directly off the wrist.

If you have ever wondered how to enable MUSIC CONTROL on your Forerunner 235, this short video shows you how.

Video 4 – Connect IQ – Widgets, Application, Data Fields & more

I made this short video during my review of the Garmin Forerunner 230/235. I realised it might be helpful to other users and potential new owners to have an understanding of how the Garmin IQ Connect works and what the difference is between WIDGETS, APPLICATIONS, DATA FIELDS and CLOCK FACES

  • CLOCK FACES are easy, the just change the look of the main Time of Day screen
  • WIDGETS are clever little APPS that are installed on the home screen. In other words, you reach them from Time of Day by pressing the DOWN arrow
  • APPLICATIONS are added with the default 4 applications of RUN / INDOOR RUN / BIKE and OTHER. When you add an application you get a new CONNECT IQ link. This takes you to the APPLICATIONS like Stopwatch or Google Maps etc.
  • DATA FIELDS are options that are added to the training page views. For example, I have added a DATA FIELD for 10K predicted race time finish. This slots in next to my regular PACE data field.

Garmin Forerunner 235 Main Features and Functions

  • Strapless Heart Rate Monitoring. HR is taken off the wrist via Garmin Elevate built-in sensor
  • Tracks Distance, Pace, Time, Heart Rate and VO2 Max
  • Provides estimated Recovery time feedback
  • Set Training alerts based on pace, speed, heart rate, time, distance and calories burnt
  • Follow advanced Workout Plans pre-programmed on Garmin Connect then downloaded to watch
  • Connected features including automatic uploads to Garmin Connect™, live tracking, audio prompts, music controls, smart notifications and social media sharing
  • Daily Activity Tracking counts daily steps, distance, calories and sleep
  • Download data fields, watch faces, widgets and applications from Connect IQ™
  • Re-broadcast of your heart rate in ANT+ (great if you have a Garmin Edge unit)
  • Battery Life – expect anything from 2 days to over a week. More about the Garmin FR235 battery life here…
  • Jump to review conclusion & summary

Differences between FR225 & the FR235

The new feautures that you will find in the Forerunner 235 that do NOT feature in the FR225 are

  • Smartphone Notifications – incoming text, social, calls and calendar alerts.
  • Music Control (control your smartphone tracks and volume)
  • VO2 Max Estimator
  • Recovery Advisor (how long until you are 100% recovered)
  • Race Predictor (estimation of your potential 5k, 10K, Half Marathon & Marathon times)
  • Bike Speed & Cadence sensor support (ANT+)
  • Training Effect (how hard a session is on a scale of 1 – 5)
  • Connect IQ functionality
  • Find My Phone
  • Garmin Elevate HR sensors (225 uses Mio’s technology)
  • Alerts – set goals on pace, speed, time, distance and calories

In other words, Garmin have packed a lot of new features in to this watch over just 18 months. Personally, I’d get the 235 as I really think TRAINING features like VO2 Max, Training Effect and Recovery advisor can play a part in getting you fitter and understanding just how hard a session really has been and making the right recovery plans.

Which Garmin Forerunner is for YOU?

Are you confused by the number Garmin Forerunners available? Don’t worry, so were we. Not surprising with over 15 models in this popular GPS running watch.

To help us and you we published this summary review of ALL the Forerunners which lists the main differences between all the models from the original Forerunner 101 in 2003 to the very latest products.

Compare the Features of the Forerunner Range

The table below shows the main differences between the Garmin Forerunner 25, 35, 235, Garmin 630 and Forerunner 735XT.

Battery Life Expectancy?

The problem with predicted the battery life expectancy on these products is the number of variables related to power consumption and how the unit is used.

If you JUST use the Forerunner 235 as an active tracker with smartphone notifications, you may well get a solid week out of it. If, however, you want to use the GPS and 24/7 heart rate monitoring then it will be considerably less.

Real World Battery life
I used this watch day in day out for 4 weeks while reviewing it. I didn’t once curse it for having a short battery life. On average, I managed to get 2 to 3 days of solid use from the unit before deciding it was time to pop it on charge.

In those 2 to 3 days, maybe 4 sometimes, I had it set to 24/7 heart rate and exercised 2 or 3 times with GPS on for 4 – 5 hours. Garmin claim it will work in GPS mode for up to 11 hours… I think that might be pushing it.

Realistically, I would be confident using the Forerunner 235 over a long weekend with up to 5 or 6 hours of GPS tracking PLUS all the other activity / smartphone / HR sampling features turned ON.

In other words, for a VAST MAJORITY of the exercising public it is more than fine.

Garmin Elevate Heart Rate accuracy

The convenience of having your heart rate acquired directly off the wrist with a set of high powered LED’s is brilliant.

Not having to find / wear a chest strap when exercising is a blessed relief. However, please note, this technology is still not 100% accurate. It’s very, very good, we’d guesstimate it’s about 95% accurate for about 95% of the time. If you want to know more, please read our reports comparing chest strap versus optical heart rate sensors.

For runners, which is the core target of the Forerunner 235, the errors are far less frequent. I intend to do a side by side comparison test soon and will link to it from here.

From my own experience the majority of issues I have witnessed has been when cycling, either MTB downhill or road riding at high speed on bumpy roads. I’m quite sure it’s the vibration of the watch unit on the wrist that causes the anomalies.

In summary, if you mainly run and don’t mind a rare HR spike / erratic reading… get the FR235, you won’t regret it.

My Workout Setup

Performing an Interval Session

Transmit Heart Rate (ANT+)

Like the Mio Fuse and the Vivosmart HR the FR235 can re-broadcast your heart rate to an other Garmin product over the ANT+ protocol.

For me, this is great. It means I can wear my 235 all day, every day, then, when out on a proper ride, the Forerunner will broadcast my exercising heart rate to my Garmin Edge 810. Remember though, it will NOT broadcast in anything but ANT+.

To enable broadcast simple press the DOWN button (from Time of Day) to get to the Heart Rate Summary Graph with live HR view.

Then PRESS and HOLD the UP button. The display will say, BROADCAST HR. All you now need to do is to enter the settings of your Garmin Edge unit and PAIR SENSOR to the FR235 as a heart rate belt.

For some reason I forgot to take a photo of this screen, sorry about that. But trust me, it works well and is easy to set up.

NOTE – you can NOT broadcast heart rate while performing in EXERCISE mode. It will only broadcast the heart rate from the front screen as detailed above. This makes sense really.

You do not want BOTH your FR235 and your Edge unit recording the same exercise set, otherwise you’d have 2 uploads to your Garmin Connect account.

Connect IQ

Garmin Connect-IQ is similar to iPhone APPS and Suunto Movescount APPS. Third parties, sometimes Garmin themselves, write APPS that cover everything from weather forecasts, watch faces and stopwatches to Google Maps.

I have really enjoyed playing with the IQ apps, although I have been a little frustrated with some that haven’t worked … ? Please watch my short video on Garmin Connect IQ to fully understand how these clever things work with the Forerunner 235.

In the images below I have shown the following from left to right:

  • An alternative ANALOGUE watch face
  • Configurable Data Field selection from the Garmin GO app
  • Selection of WATCH FACES
  • A 10K Race Time Predictor that makes up a DATA FIELD within your training views
  • A very comprehensive WATCH FACE which attempts to show everything in one view… sorry… don’t like it, can’t see it !
  • A Google Maps APPLICATION – unfortunately, I couldn’t get it to work
  • A very effect STOPWATCH APPLICATION – that works like a treat.

Top Alternatives

Next Model UP

Garmin have released the Garmin Forerunner 645 with internal music store, 24/7 Heart Rate, Stress Testing and more.

This new model is aimed at serious athletes looking for an all round performance monitor.

The Forerunner 645 features GPS, wrist based heart rate and built-in music store with Bluetooth connectivity to compatible headphones …

Next Model DOWN

The next model down from the 235 is really the Forerunner 35. The FR35 features Garmin Elevate wrist based heart rate as per this Forerunner 235.

However, it’s a very different style of watch being rectangular with a monochrome display.

The Forerunner 35 is aimed for the mass of running enthusiasts who do NOT want to get involved in VO2 Max predictions, Recovery Analysis or add Garmin Connect IQ widgets and apps.

Garmin Forerunner 235 Review Summary

Without clutching for straws there is nothing to criticise in this near perfect GPS runners watch. The Garmin Forerunner 235 is simply brilliant.

Not just a GPS running watch of the finest pedigree it’s also a competent activity tracker with 24/7 activity and heart rate tracking and Garmin IQ connected smartwatch.

I’ve no doubt there will some day be a better GPS watch designed specifically for runners, but presently, for those looking for a running watch with wrist based heart rate, built-in GPS, smartphone connectivity and 24/7 activity tracking it a 5/5 star rating from me.

Update June 2021 > Garmin have released the Garmin Forerunner 645 with internal music store, 24/7 Heart Rate, Stress Testing and more.

This new model is aimed at serious athletes looking for an all round performance monitor.

The Forerunner 645 features GPS, wrist based heart rate and built-in music store with Bluetooth connectivity to headphones …

>> Check out our list of best watches for adventure!

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