6 Best Cast Iron Dumbbells in 2024

In this article, I’ve picked the top cast iron adjustable dumbbells for lifting and comprehensively reviewed them so you don’t have to. I’ll look at the features, materials, design and give the pros and cons of each brand.

Dumbbells belong to the free weight family alongside barbells and kettlebells. Unlike fixed path resistance machines, they are free moving depending on how you move your body. They consist of a central handle with weighted heads at each side which vary in shape, diameter, and thickness. It’s these characteristics that determine the dumbbell weight, usually in pounds, half pounds, or kilograms.

Dumbbells are a great addition to your home gym set-up. You can train a wide range of full-body or accessory movements effectively. Dumbbells force you to train unilaterally, meaning you can work on muscular imbalances and target specific muscle groups that you may need to focus on, increasing strength and improving your lifts.

With so many dumbbells available to buy, it’s hard to know what to choose. Dumbbells can range in features, size, adjustments, and price. In this article I’ve reviewed the best cast iron dumbbell sets looking at weight selection, design, materials, and quality, taking out the hard work and helping you to make a good choice.

So dumbbells are versatile, don’t take up much room, and are relatively cheap compared to other home gym equipment. Let’s take a look at my top picks.

Top 6 Best Cast Iron Dumbbells Reviewed

1. Rep Adjustable Dumbbells – Top pick
2. CAP Barbell Adjustable Cast Iron Dumbbell Set – Runner up
3. Yes4All Adjustable Dumbbell Set
4. Papababe Dumbbells Weight Set – Best set
5. WF Athletic Supply Dumbbells
6. Powergainz Adjustable Dumbbell Set

Product	Total	Weight Range	Weight Increments	Design	Materials	Quality	Price
REP Fitness	57	10	10	9	9	10	9
CAP	55	9	9	9	9	10	9
Yes4All	53	8	9	9	9	9	9
Papababe	52	9	8	8.5	8.5	9	9
WF Athletic	51	8.5	8	8.5	9	9	8
Powergainz	50	8	8	8	9	9	8

1. Rep Adjustable Dumbbells – Top Pick

• Weight Range: 85 lbs total max weight for each dumbbell
• Weight Increments: 8 x 10 lb plates (four on each side)
• Dimensions (LxWxH): 17.5 x 6.5 x 5 inches
• Adjustment System: Star lock collars with rubber O-rings, threaded handle ends
• Materials: Cast iron weight plates with black epoxy finish, solid steel handle with diamond knurled chrome finish
• Warranty: 1-year 

The top pick comes from REP with their Adjustable Dumbbells set. These are made from the highest-quality materials meaning that you’re already getting the best and long-lasting product.

To further that, you get to choose from two options when purchasing — a 20lb pair (two handles, four-star collars with rubber bands, and four 2.5 lb plates) or the 52.5lb pair (two handles, four collars, sixteen 5 lb plates, four 2.5 lb plates, and four 1.25 lb plates). You also have the choice of adding a 40 lb weight upgrade where you get 4 10 lb plates.

The maximum that you can stack on one dumbbell is 85 lbs, including the 4 lb handle and two 0.5 lb start collars.

The only thing that could be improved is the fact that, regardless of the rubber band that is designed to prevent unscrewing, the collars still tend to get loose sometimes.

To top things off, you get a 1-year warranty, proving REP’s confidence in their own products.

These adjustable-weight dumbbells offer an amazing weight range for all levels.

2. CAP Barbell Adjustable Dumbbell Set – Runner Up

• Weight Range: 52.5 lbs total max weight each dumbbell
• Weight Increments: 2 x 1.25 lb plates, 2 x 2.5 lb plates, 8 x 5 lb plates
• Dimensions (LxWxH): 16 x 6.5 x 6.5 inches
• Adjustment System: Star lock collars with rubber O-rings, threaded handle ends
• Materials: Cast iron weight plates with black epoxy finish, solid steel handle with diamond knurled chrome finish
• Warranty: 30 days

CAP Barbell was founded in 1982 and produces a wide range of fitness equipment. The CAP Barbell brand prides itself on producing high-quality products at great prices.

It cuts production costs by strategically placing distribution centers at good locations around the world.

If you're looking for a high-quality durable set of dumbbells, the CAP Barbell cast iron adjustable dumbbells are a great option and are my top pick.

The dumbbells go up to 52.5 lbs each and come with 1.25, 2.5, and 5 lb plates, giving a range of weight options for different exercises.

Both the dumbbell handle and weight plates are rust-resistant and made from steel and cast iron. The cast iron plates are covered with a black epoxy finish to prevent corrosion. The 17-inch handle is crafted from steel with diamond textured knurling.

The dumbbells are adjusted using star-lock collars with rubber O-rings which screw onto the threaded dumbbell ends. The adjustable nature of the dumbbells eliminates the need for multiple different dumbbell weights.

The compact design of the dumbbells makes them easy to use and store at home.

3. Yes4All Adjustable Dumbbell Set 

• Weight Range: 40-200 lbs max weight for 2 dumbbells
• Weight Increments: 2.5, 3, 5, 7.5 and 10 lb plates depending on dumbbell weight choice
• Dimensions (LxWxH), depends on weight choice: 40 lbs: 13.8 x 12.5 x 12.5 inches, 200 lbs 22.5 x 11.5 x 11.5 inches
• Adjustment System: Star lock collars with rubber trims, threaded dumbbell ends
• Materials: Cast iron weight plates with black paint finish, steel handle with diamond knurled chrome finish
• Warranty: 60-day return, 5 year warranty

Yes4All was founded in 2010 and is one of the leading brands of home sporting goods. Rather than selling products, the brand motto states they sell experience by providing everything for people to get fit at home.

The brand motto is ‘Be Incredible’. They believe strengthening health should be for everyone to enjoy and are committed to offering the finest products available at a reasonable price point.

So, in the runner-up position are the dumbbells by Yes4All. The dumbbells have a large weight range going from 40-200 lbs. The weight plates are dependent on the dumbbells and include 2.5, 3, 5, 7.5, and 10lbs catering to a wide range of needs.

The 16-inch handle is made from steel and knurled to help with grip. The weight plates are made from cast iron and powder coated with black paint to prevent rust.

The dumbbells feature threaded ends and star-lock collars with rubber trims. The dumbbells are compact and easy to use with a wide range of weight options eliminating the need for multiple dumbbells at home.

4. Papababe Dumbbells Weight Set – Best Set

• Weight Range: 150 lbs dumbbell set total weight
• Weight Increments: 2 x 5, 10, 15, 20 and 25 lb dumbbells
• Dimensions (LxWxH): N/A
• Adjustment System: Rack with set dumbbell weight options
• Materials: Cast iron free weights with rubber casing
• Warranty: 30 days 

If you're looking to buy a cast iron dumbbell set without worrying about adjusting the weight after each exercise, papababe offers a good dumbbell set and rack package.

Papababe manufactures and sells a wide range of commercial and at-home gym equipment. Its brand values are easy to start, highly efficient to workout, and energize your energy.

If you're wanting different weight choices without having to change the plates, the dumbbell and rack combination by papababe would be my pick for the best set available online.

The set comes with 5 sets of dumbbells which range from 5-25 lbs, providing a good range of weight options.

The dumbbells are made from solid cast iron encased in rubber helping to protect your floor in your at-home gym. The hexagon head design helps to prevent rolling and makes them easy to store if needed.

The dumbbell handle is designed with a knurled finish for comfort and safety and helps to provide a stronger grip. Each dumbbell is clearly marked with the amount of weight and is made of natural rubber.

The compact design of the included rack makes the cast iron free weights easy to put away after use and makes the A-frame easy to place in your home gym.

5. WF Athletic Supply Dumbbells

• Weight Range: 1-120 lbs
• Weight Increments: 1, 2, 3, 5, 8, 10, 12, 15 lbs, 20-120 lbs in 5 lb increments
• Dimensions (LxW), depends on weight: 20 lbs: 10.98 L x 4.57 W inches
• Adjustment System: Set non-adjustable weight options
• Materials: Cast iron dumbbell heads with steel handle
• Warranty: 30 days

WF Athletic Supply supplies a wide range of high-quality fitness equipment. The brand is committed to helping athletes at all levels succeed in sport by providing the best strength, conditioning, speed, and agility equipment.

WF Athletic Supply aims to improve athleticism, develop discipline and achieve success with a well-trained mind and body.

If you're looking for high-quality dumbbells made by a proven brand, the dumbbells by WF Athletic Supply are very well made. The dumbbells have an excellent range of 1-120 lbs. They go up in 1 lb increments until 15 lbs after which they go up in 5 lb increments providing weight options for beginner and elite-level lifters.

The hexagon-shaped dumbbell heads prevent rolling and the medium depth knurling on the handle provides a secure grip during use. The semi-gloss finish helps to prevent rusting.

The dumbbell heads are made with cast iron and the handles are made from steel to give a solid durable construction.

6. Powergainz Adjustable Dumbbell Set

• Weight Range: 40-105 lbs max weight for 2 dumbbells
• Weight Increments, depends on dumbbell weight: 40 lbs: 4 x 3 lb plates, 4 x 5 lb plates, 105 lbs: 4 x 1.25 lb plates, 4 x 2.5 lb plates, 16 x 5 lb plates
• Dimensions (LxWxH): N/A
• Adjustment System: Star-lock collars with rubber trims, threaded dumbbell ends
• Materials: Cast iron dumbbell plates, contoured steel handles
• Warranty: 30 days

Powergainz sells its products in the strength training and fitness category, mainly including dumbbells and barbells. The brand has a good reputation, with an average of 4.3/ 5 stars on amazon.

Powergainz sells a well-manufactured dumbbell set made from high-quality materials. The dumbbell sets have 2 options of 40 lbs and 105 lbs. The 40 lb set goes up in 3 and 5 lb increments and the 105 lb set goes up in 1.25, 2.5, and 5 lb increments.

The round-shaped dumbbells are made with cast iron plates and contoured steel handles.

Why Are Dumbbells Made of Cast Iron?

Dumbbells come in all shapes and sizes but are usually made from two main materials, rubber, and cast iron. Cast iron has been used to manufacture metal dumbbells for generations and is still widely used in the gym and at home.

The metal dumbbells are produced through a casting process where cast iron is melted and then poured into a mold to create the solid casting. There are two types of cast iron dumbbells. The fixed dumbbells feature a short handle with a hexagon or round iron cast weight at each giving a certain weight option depending on the amount of iron used. The adjustable ones consist of cast iron weight plates mounted on a handle by movable screws allowing the weight to be adjusted as needed.

Dumbbells are made of cast iron as they can be made to suit different lifter needs based on design, types, and weight distribution. The high-quality manufacturing process makes the dumbbell durable, meaning it can last a lifetime if used correctly. The cast iron material also gives the dumbbells an old-school feel, adding to your lifting experience.

Cast Iron Dumbbell Benefits – Why use them?

1. Extremely Durable

Cast iron dumbbells are made using a high-quality manufacturing process where the cast is checked for defects that may impact performance and durability. As long as the dumbbells are used correctly, they will last a lifetime.

2. Increased Stabilization And Muscle Activation

Dumbbells are classed as free weights. This means they move freely depending on the way you activate your muscles. Compared to fixed path resistance machines, dumbbells need greater stabilization to perform a given movement correctly. This means your body needs to work harder by recruiting a greater number of muscle fibers.

3. Helps To Correct Muscular Imbalances

If you need to target a specific muscle group or work on a muscular imbalance, dumbbells are a great choice. Dumbbells force your limbs to work unilaterally, meaning it's harder to overcompensate with a certain muscle group or side of your body.

4. Easier To Grip

When you're working hard performing high repetition or high-intensity exercises, the last thing you want to think about is making sure the dumbbells don't slip out of your hands. The anti-slip handle design of cast iron dumbbells makes them easier to grip compared with other dumbbell materials.

5. Old School Design

This isn't as important but simply put, cast iron dumbbells look good. The cast iron dumbbells are good to look at and provide the user with an old-school feel. If you enjoy lifting and listening to the sound of the iron plates clanging together, these are a great choice.

6. Who Needs Dumbbells?

If you're a lifter who enjoys performing unilateral movements during your workouts, dumbbells are a great option. They help to target specific muscle groups by providing a free movement pattern, allowing you to work on any muscular imbalances or weaknesses you may have.

Dumbbells can be used to perform a wide range of unilateral movements working the full body and cater to different goals. Dumbbells can compliment compound movements using fixed resistance machines or other free weights, provide an added stimulus with a more challenging movement pattern and range of motion, or be used for more sports-specific functional training to improve performance.

When shopping for cast iron dumbbells there are a few things to look out for if you want to grab the best deal for you.

When working with a dumbbell you want different weights for different muscle groups. The reason for that is, for example, that your maximum weight for the biceps can be your warm-up weight for the dumbbell bench press exercise. If you’re an intermediate lifter, jumping from 25 lbs to 50 lbs might not be the ideal situation for everyone. Instead, it is often better to have the option to increase the weights in smaller increments. This gives you a plethora of options when it comes to workouts. From targeting different muscle groups more precisely and effectively, to increasing weights in small chunks between sets — you have them all.

Depending on your gym size and storage area, it can be a benefit to opt for smaller dumbbells instead of bulky ones

If you aren’t able to swiftly and without hassle change the composition of the plates on each handle, then you might find yourself stressing over it. Consider getting adjustable dumbbells that can be adjusted easily.

4. Material

Get high-quality materials since you want the dumbbells to last you a long time. Also, see that if they are iron cast or made of steel, they are properly coated with something that won’t get scratched or flake off easily.

5. Warranty

You never know what might happen with your gym equipment, and having that peace of mind in the form of a manufacturer's warranty can be a game-changer in case you encounter such an issue.

6. Price

Everyone has a budget in mind. Think of that first, and see what’s available out there on the market. Pick the dumbbell product that will cover your needs the best without compromising on quality (or at least as close as you can get to that).

7. User Reviews

If you still cannot make up your mind or are in doubt about which of the two products to buy, then consider checking user reviews. These can sometimes be misleading, but can also be a promising source of vital information, which will ultimately lead you to make a more informed decision.

8. Brand Reputation

Brand reputation itself can be a powerful indicator of whether a product is good or bad. This is not always the case. But consider the fact that if a brand is reputable, what are the chances that it will intentionally try to harm its hard-built reputation by placing a low-quality product on its shelves?

FAQ

Do Cast Iron Dumbbells Break?

During the process of making cast iron dumbbells, the cast iron is analyzed and the end product is checked to ensure quality construction.

Cast iron dumbbells are made to last. Unless you're leaving them outside all the time or dropping them consistently, you can expect them to last for as long as you use them.

Are Cast Iron Dumbbells Toxic?

Cast iron dumbbells are considered as non-toxic and safe for use in your home gym. Most cast iron dumbbells are manufactured using only cast iron with some containing a thin layer of rubber, only harmful if ingested. As always, make sure to use the dumbbells as directed and keep away from small children or pets if you're concerned.

Are Iron Dumbbells Better than Rubber?

Both dumbbell types can be used with success with some key differences that may make iron dumbbells the better choice. If you're allergic to latex or sensitive to strong smells, iron may be the better choice. Whilst the rubber coating isn't toxic if you don't ingest it, using iron dumbbells can fully eliminate this worry. Cast iron dumbbells may cost more but they are built to last a lifetime and give a more aesthetic gym feel.

Are Cast Iron Dumbbells Heavier?

All dumbbells, regardless of type, are weight tested to make sure they are the correct weight before being sold for use at commercial gyms or home.

Dumbbell design, weight distribution, design, and amount of use are all factors that can affect how heavy cast iron dumbbells can feel in comparison to other dumbbell types.

Which Cast Iron Dumbbells Are the Best?

Adding dumbbells to your home workout setup is a great idea. You can perform a wide range of compound or accessory unilateral movements to increase muscular size and strength, improve sports performance, or address muscular imbalances.

Iron cast dumbbells are constructed to last a lifetime, going through a rigorous testing process during construction. They can be fixed or adjustable, making them useful for a wide range of gym movements. They are easy to grip and look great in the home gym, giving an old-school feel.

The REP Fitness cast iron dumbbell set is my top pick, getting the highest score for weight selection, design, materials, and quality.

What do you think of the dumbbells I've reviewed above? Share your experiences and ask me any questions in the comments below.

Also read:

• Best Cheap Dumbbells
• Best Neoprene Dumbbells
• Best Olympic Dumbbell Handles
• Best Rubber Hex Dumbbells
• Best Urethane Dumbbells
• Metal Dumbbells vs Rubber
• Heaviest Adjustable Dumbbells
• Best Home Gym Dumbbells

References:

1. "What Are Dumbbells Made Of?" YogaFitness, https://www.yogafitness.group/what-are-dumbbells-made-of/#II_Cast_Iron_Dumbbell
2. Ha Nguyen, "What are dumbbells made of? Vinyl vs. Cast iron vs. Rubber" Vietnamcastiron, https://vietnamcastiron.com/dumbbell-materials/#what-is-cast-iron-dumbbell
3. Andrew White, "How Are Dumbbells Made?" GarageGymPro, https://garagegympro.com/how-are-dumbbells-made/ (January 6, 2022)
4. "Dumbbell" Wiki, https://en.wikipedia.org/wiki/Dumbbell (18 June 2023)
5. Rebecca A. Seguin, "Growing Stronger" CDC, https://www.cdc.gov/physicalactivity/downloads/growing_stronger.pdf (2002)
6. Dirk Aerenhouts, "Using Machines or Free Weights for Resistance Training in Novice Males? A Randomized Parallel Trial" NCBI, https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7662789/ (17(21): 7848.)