Live Science Verdict
At the touch of a button these smart adjustable dumbbells change weight in seconds. They do the basics brilliantly: the plates slotting securely into place and the compact, rounded shape making them easy to maneuver. The design is sleek and screams premium quality, and they have features such as app connectivity and virtual rep counting – something technology-lovers will enjoy.
Sleek, sturdy design
Changing weight is effortless
Smart features including app connectivity
Need to be charged up to work
Screen on the holding dock can be hard to see
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As one of the world’s first digital dumbbells, the JaxJox DumbbellConnect represents a big change when it comes to home workout equipment, and we think it’s done a mighty fine job.
Initially, we were skeptical about the need to reimagine the dumbbell, with the idea of a free weight loaded with Bluetooth and app connectivity sounding like something from Back To The Future. But, getting our hands on a pair, we found that JaxJox has made it work – so much so that its revolutionary weights earned top spot in our tried-and-tested roundup of the best adjustable dumbbells and best workout equipment for home workouts.
Weight range: 8lb-50lb (3.6kg-22.7kg)
Handle size:: 19.5in (L) x 7.5in (W) x 7in (H) (49.5cm x 19cm x 17.7cm)
Base size:: 19.5in (L) x 7.5in (W) x 5in (H) (49.5cm x 19cm x 12.7cm)
Warranty: One year
The key to the DumbbellConnect’s success is their ability to do the basics well. At the heart of this forward-thinking product is a pair of sleek, sturdy dumbbells that look and feel great. The plates lock into place securely, the handles are grooved for great grip and their shape never feels unwieldy.
Each dumbbell loads into a docking station with a small LED screen on the base displaying the weight. Using plus and minus buttons either side of the screen, you can adjust the load digitally from 8lb to 50lb per dumbbell (in 6lb increments). This means you get eight weights in one compact package so, especially if you pair it with one of the best yoga mats, you can enjoy an oven-ready home gym set-up. It also provides the perfect tool for utilizing the progressive overload principle to optimize your muscle-building, and means you don't have to endure the hassle of manually loading and stripping plates between sets.
The ability to link to an app – where the dumbbells will count your reps, and there are a selection of follow-along workouts to try – is a fun extra that adds great value to the dumbbells. But, the reason the JaxJox DumbbellConnect triumphed in our test of the best adjustable dumbbells is down to their unrivaled functionality as free weights.
Price and release date
One of the only digital adjustable dumbbells available, the JaxJox DumbbellConnect was launched in spring 2021. The dumbbells are sold as a pair and retail for $499 or £499.
There are many workouts you can do with two dumbbells, including a weights at home workout. But, if you’re looking for extra exercise inspiration, you can subscribe to the JaxJox app for £12.99 or $12.99 a month, after a free 30-day trial. This offers a collection of on-demand, follow-along workouts, and links to your dumbbells to offer real-time performance stats.
Set up and ease of use
- Simple set-up
- Intuitive to assemble and use
- Have to be charged up to work
With the tech-heavy features on offer, it would have been easy for JaxJox to over-complicate the DumbbellConnect. However, even compared with other adjustable dumbbells, we found the setup simple.
There are 20 pieces in the box; two handles, 14 plates, two docking stations and two USB-C charging cords. Once we had charged the docks, all that was left to do was load the plates into them, add the handles, and we were good to go.
When the docks automatically recognised the dumbbells were present, we were then able to adjust the weight using the plus and minus buttons either side of the small LED screen on the foot of the base.
One drawback of the digital dumbbell model is that, if you allow the base to run out of charge, you won’t be able to change the weight. However, you can top up the battery in a couple of hours and a full charge will last well over a week.
- Sleek aesthetic
- Sturdy feel
- Compact, easy to store design
The JaxJox DumbbellConnect delivers on the MO of adjustable dumbbells: providing the function of several differently weighted dumbbells in one compact package. What’s more, they do it in style, with the matt gray finish and green trim around the base of the docking station creating a sleek, stylish aesthetic.
Unlike some adjustable dumbbells, they don’t rely on wide, unwieldy plates to provide a range of weight options. The DumbellConnect’s rounded plates are uniform in circumference and, at 6.7in wide, they never felt awkward or got in the way when we performed exercises like dumbbell chest press or alternating curls.
The plates sit flush against one another, adding to the tidy finish and preventing them from moving or rattling when we used them. We also liked the inclusion of one flat edge, so you can place the dumbbells on the ground between sets without having to worry about them rolling away. This flat platform also allowed us to perform exercises like renegade rows or use them as push-up stands, which was a welcome bonus.
Each docking station is 19.5in long, 7.5in wide and 5in tall, so the pair can be stored neatly and discreetly, and the small LCD screen on the foot of each base is bright and minimalistic; the current weight setting takes up most of the screen, with the battery levels of the handles and docking stations, and changeable unit of measurement (lb or kg), displayed above it.
If you store them on the floor, the positioning of the screen can be awkward to see, but this is a minor gripe. The two-button system for shifting the weight is intuitive to use, and we found removing and re-racking the weights to be a seamless experience.
Features and functionality
- Choice of eight weight settings from 8lb-50lb
- Digital weight changing
- App connectivity
With a weight range of 8lb-50lb (3.6kg-22.6kg) per dumbbell, the JaxJox Dumbbell Connect has enough settings to satisfy most exercisers.
The handle alone weighs 8lbs (3.6kg), then you can add plates digitally to increase the load in 6lb (2.72kg) increments. This is great for more-experienced lifters, though beginners may want smaller increases (such as the 2.5lb jumps offered by the Bowflex SelectTech 552) so they can make more gradual progressions as their strength builds.
The LED screen and two-button system for adjusting the weight is easy to use, and once we selected the appropriate load it took less than five seconds to change. This is great for training methods where you might need to use two different weights one after the other, such as supersets or drop sets, as it allows you to quickly shift the weight and move on to the next exercise with little delay.
The fact you have to cycle through each of the weight options in ascending or descending order to get to the right one slows things down slightly, but the JaxJox DumbbellConnect transition time will still leave traditional spinlock dumbbells in their dust.
You can link the weights to the JaxJox app via Bluetooth to provide real-time feedback on metrics, such as your number of reps. However, while this is fun to play around with, we found it more of a gimmick than a feature we would regularly use.
- Changing the weight takes seconds
- Comfortable to use
- Great grip on the handles
This is where the JaxJox Dumbbell Connect adjustable dumbbells come into their own. The metal plates and matt gray finish combine to create a visually pleasing package, but this wasn’t a case of style over substance.
Each holding dock takes up a 19.5in by 7.5in patch of floor space, so they can easily be stored when not in use. And, the compact circular shape of the plates means they don’t get in the way when performing lifts like bicep curls.
The way the plates connect (sliding together like pieces of a jigsaw before being reinforced with a central metal bar that extends from the handle) means they sit tight against one another. This provided the most secure feeling of any adjustable dumbbell we tried, making us feel comfortable pressing them overhead without worrying a stray plate might come loose. It also meant they were whisper quiet, with no signs of the rattling or clanging of metal plates that regular gym-goers will be all too familiar with.
The knurling (grooves) on the metal handles provided sufficient grip so the dumbbells never slipped in our hands, even during sweatier sessions. However, it wasn’t cut so deep that it ever felt uncomfortable. We also liked the plastic bumpers between the handles and plates as these made the dumbbells comfortable to hold in the goblet position – a handy tool for lower body movements like squats and lunges.
During our tests we found some adjustable dumbbells, such as the more affordable Core Fitness weights, could be difficult to load and unload from their holding docks due to their plates moving around. But, there was no such problem with the JaxJox DumbbellConnect pair, which slipped into place whatever weight we were using.
Changing the weight was simple too, saving time and effort between sets. Having to scroll through the available weight options in numerical order made this process less streamlined, but only added a few seconds to the transition time.
JaxJox asks users not to drop these weights, so they may not be suitable for training styles like CrossFit. However, for HIIT and resistance training at home, you’ll struggle to find a better adjustable dumbbell.
Value for money
The retail price of an adjustable dumbbell (in this case $499 or £499) may raise a few eyebrows at first, but if you break the cost down then the investment starts to make a lot of sense.
With the JaxJox DumbbellConnect, you’re essentially buying a rack of eight dumbbells. Unlike some adjustable dumbbells, they also come as a pair (perfect for efficiently training both sides of the body at once).
Buying eight pairs of fixed-weight dumbbells is likely to set you back a pretty penny. And, with a variety of differently-loaded dumbbells at your disposal, you can switch from gym-based to at-home training, saving money on your former monthly membership.
So, with their premium performance and added space-savvy benefits, we think the JaxJox DumbbellConnect adjustable dumbbells are well worth their asking price.
The JaxJox DumbellConnect is the crème de la crème of adjustable dumbbells, balancing innovation with tried-and-tested training methods to deliver a brilliantly versatile tool for at-home exercise.
They come as a pair, with eight weight options that you can switch between in seconds via the digital docking station, and have the equivalent footprint of a footstool, making them a time and space-efficient option for any sans-gym fitness routine.
We were impressed by their sleek matt gray finish and premium materials, with the metal plates and handle giving the weights a robust feel. Whatever load we selected, they felt solid and secure, while their compact, rounded shape makes them easy to wield during exercise.
If this isn't for you
If you’re sold on the idea of adjustable dumbbells but don’t feel you need all the bells and whistles (and expense) of a digital model, the Core Home Fitness Adjustable Dumbbells are a more-affordable alternative.
Or, if you’re new to resistance training and want a dumbbell that offers smaller jumps in weight, allowing you to apply progressive overload to your lifts, the Bowflex SelectTech 552 may be the free weight for you.
Harry Bullmore is a fitness writer covering everything from reviews to features for LiveScience, T3, TechRadar, Fit&Well and more. So, whether you’re looking for a new fitness tracker or wondering how to shave seconds off your 5K PB, chances are he’s written something to help you improve your training.
When not writing, he’s most likely to be found experimenting with a wide variety of training methods in his home gym or trying to exhaust his ever-energetic puppy.
Prior to joining Future, Harry wrote health and fitness product reviews for publications including Men’s Health, Women’s Health and Runner’s World. Before this, he spent three years as a news reporter with work in more than 70 national and regional newspapers.