Garmin Forerunner 305 vs 405
December 23, 2011 by Jacquie
Filed under Running Advise & Opinions, Running Equipment
My husband and I decided to buy the Garmin Forerunner 305 for ourselves for Christmas. We found such a cheap price for the Garmin Forerunner 305 that we just didn’t want to pass up on the opportunity. It’s been too many too many years since my old heart rate monitor, the Polar Beat has been fully functioning and with my quest to qualify for the Boston Marathon, we thought that it was time to take the plunge.
When I started researching and reading reviews for the heart rate monitors, I came across the best price for the Garmin 305 at Amazon. This was a couple years ago and the Garmin Forerunner 305 was cheaper than it is today. I couldn’t believe that I could get a heart rate monitor and a GPS system (and more) for the same price as what I would pay for a decent heart rate monitor. Just for curiosity , I dug out my old Polar Beat heart rate monitor (that was year’s old) and on the box it had a price of $139.99. The Beat never had any features – no target heart rate, average heart rate or upper and lower limits. Just a plain and simple heart rate monitor which was actually very useful to my training in it’s day.
Now that I was interested in GPS systems instead of a simple heart rate monitor, I thought I should compare the Garmin Forerunner 305 vs 405. At the time of writing this, the Garmin Forerunner 405 was slightly out of our price range at $349.99, and I’m not sure why, but they sure have come down a lot in price over the last 2 years.
Because of the price difference, we chose to buy the Garmin Forerunner 305, but I still wanted to compare the two units. The easiest way for me to compare the technology of the two GPS/heart rate monitor systems was to draw up a table, which I would like to share:
Garmin Forerunner 405 vs 305 – A Comparison
![]() |
![]() |
|
| Features | Garmin Forerunner 305 | Garmin Forerunner 405 |
| Weight | 2.72 oz | 2.11 oz |
| Dimensions (WxHxD) | 2.1” x 2.7” x 0.7” | 1.9” x 2.8” x .65” |
| Display size | 1.3” x 0.8” | 1.06 diameter |
| Water Resistance | Yes | Yes |
| Battery Life | 10 hours | 8 hours |
| Calories burned | Yes | Yes |
| Lap heart rate | Yes | Yes |
| Average heart rate | Yes | Yes |
| Heart rate zones | Yes | Yes |
| Time/distance alarm | Yes | Yes |
| Pace alert | Yes | Yes |
| Interval training | Yes | Yes |
| Auto lap | Yes | Yes |
| Auto pause | Yes | Yes |
| Lap history | stores 1000 laps | stores 1000 laps |
| Waypoints/favorites | stores 100 locations | stores 100 locations |
| Routes | stores 50 routes | No |
| Virtual Partner | Yes | Yes |
| Backlight | Yes | Yes |
| Wireless heartrate transmitter | Yes | Yes |
| Sport watch | No | Yes |
| Unit to unit/PC transfer (shares data wirelessly with support of USB ANT stick) | No | Yes |
Differences Between Garmin Forerunner 305 and 405
The biggest seen difference of the two units was the size. Some don’t like that the Garmin 305 is bulky, however those that use it say that it is very comfortable to wear.
The 405 has a whole different look and feel in that instead of the square bulky look, it is round and looks like a watch and could double for a watch, since it has all the sport watch features. Surrounding the watch face is a touch bezel that allows the user to scroll through the functions screens, unlike the 305 that is operated through push buttons. Though user reviews felt that the touch bezel was awkward to operate.
The navigation capabilities were comparable on both units. They both let you mark or find locations and also navigate you back to your starting point. I think that this will be a very nice feature if you go for a run anywhere that is unfamiliar and there is the possibility of getting lost. This would definitely let me be more adventuresome in my route planning.
After reading multiple reviews of both units, it was clear to me that the Garmin 305 was a very well liked product. It performed well and would work great for our needs. And compared to the Polar Beat – well, there is no comparison. We bought our Garmin Forerunner 305 through Amazon a couple years ago. I have put it to the test and have written a very detailed Forerunner 305 review.
Related Articles
- A Recent Poll Reveals the Top 3 Running Accessories - We runners don't ask for much. For many years we plied our trade in nothing more than shorts, shirts ...
- How to Use a Running Watch - Owning a running watch and using a running watch are completely different and the reason being is th ...
- Treadmill Buyers Guide - Purchasing the Best Treadmills Once you've decided to purchase a treadmill , now what? Time to get ...
- Training Tips – Add Variety to Your Run Routine - If you are like most runners, you follow a run routine and that you don’t typically deviate from. ...
- Run Faster - During my last couple runs I've had the opportunity to run with one of our city's Marathon Clinic ru ...





Rob, StrideFit Personal Trainer, Brighton on Fri, 27th Jan 2012 2:49 pm
Like the review! I’ve owned many different heart rate monitors – all of which have gradually faded and died – and decided this Christmas to make the jump up to a GPS/HR unit.
I bought the 405 because a) it was on offer and b) it looked more compact and watch-like so I would probably get away with wearing it like a watch (vain I know). The 405 is great but there are a load of things that grate about it – I almost regret not getting the 305!
I’m hoping to integrate it into some of the personal training sessions soon.
I’m writing a review on it this week on my PT blog. Come and check it out.