What the dumbbell is made of affects both its longevity and your floor’s safety.

A weight that challenges you at 5–8 reps for compound movements like goblet squats or rows. 4. Where to Buy

Specialized fitness retailers (Rogue, Rep Fitness) offer the highest quality, while big-box stores (Target, Walmart) are convenient for basic hex weights.

Check local marketplaces like Facebook or Craigslist. Iron doesn’t "expire," so buying used is the best way to get quality gear at nearly half the price—just check for excessive rust or loose handles.

These use a dial, pin, or plate system to change weights. They are the ultimate space-savers. While they have a higher upfront cost and can be slightly more fragile due to their internal mechanisms, one pair can replace an entire rack of 15+ sets. 2. Material and Grip

Your "workhorse" weight for 8–12 reps of curls or overhead presses.

A weight you can press or curl for 15+ reps. Good for lateral raises and warming up.

These are what you see in commercial gyms. They are durable, easy to grab, and perfect for supersets where you need to switch weights fast. However, they require a lot of floor space and get expensive as you buy more increments.