What Is A Smith Machine?

A Smith machine is a weight-lifting apparatus where the barbell travels up and down along steel rails. The guide rails restrict the weight to a vertical (or near-vertical) movement, making it somewhat safer than free weights.

Each end of the bar has a hook that rotates, and there are a series of lockout points at which you can hook the weight. These hooks mean the Smith machine can be a sort of “self-spotting” device, which also increases safety.

By removing the need to stabilize the bar, Smith machines put more of the load on the primary muscles targeted by each exercise. And the fixed movement path can be an excellent way to mix up your routine.

Another feature of Smith machines is that they have a lower starting weight than Olympic barbells. But the actual weight of the bar depends on a couple of factors. So let’s dive into Smith machine bar weight.

How Much Does A Smith Machine Bar Weigh?

A Smith machine bar weighs anywhere from 6 lbs to 32 lbs depending on the construction material, counterbalancing, and the angle of the rails.

Bar Materials

Some smith machine bars are lighter than a standard 45 lb Olympic bar because they’re not high-strength steel. But with supports on each end, the bar doesn’t undergo the bending stress seen by a free-weight bar.

Therefore, the bar itself may weigh 30-40 lbs. Although sometimes, it can weigh more due to the added bearings and hooks.

Counterbalancing

In addition, Smith machine bars are often counterbalanced, meaning the bar is made to feel lighter through a system of cables, pulleys, and counterweights.

Usually, this counterbalance system is hidden behind safety covers, but the image below is what it looks like inside.

With a counterbalance, the perceived weight of a Smith machine bar is usually less than 30 lbs. But it could be as low as 6 lbs depending on the balancing use.

But why counterbalance the bar at all? The reason is to lower the starting weight of the bar for people new to training or for exercises where a lighter load is preferred.

Ok, so why not make the bar weigh 0 lbs? Well, if machine makers balanced the bar with an equal counterweight, the slightest touch would send it up to the top of the machine. Like an astronaut in zero gravity!

But this free-floating bar could damage the machine. Therefore, Smith machine manufacturers counterbalance the bar, so it has some weight but not as much as a traditional barbell.

Angle of Rails

Some Smith machines have guide rails angled to match better the natural movement path for exercises like squats and the bench press. And the rails’ incline can change the bar’s weight slightly.

In physics class, you may have drawn force diagrams like the one below. This drawing represents the forces acting on an object resting on an incline.

Common Smith Machine Bar Weights

So far, we’ve established that Smith machine bars can weigh anywhere from 6 to 32 lbs depending on the type of Smith machine you have. So to help you narrow that down, I’ve split that up into two common Smith machine types.

Residential Smith Machines

A residential Smith machine is one that you might purchase for your home gym. Typically they are made of cheaper materials and cost $1,000-$2,000.

Often a residential Smith machine has a standard barbell with a 1″ diameter as opposed to the 2″ diameter of Olympic bars and plates. However, they do sell adapters so that you can use Olympic plates.

In addition, the bar is usually not counterbalanced. So, while the bar is lighter steel than an Olympic bar, you feel the total weight. That means residential Smith machines can have a starting weight of around 30 lbs.

Another common cost-saving area is the slide mechanism for the bar on the rails. Residential Smith machines sometimes use nylon bushings instead of ball bearings, so it’s not as smooth as a commercial Smith machine.

Commercial Smith Machines

On the other hand, a commercial Smith machine is one you would find in a large gym. It is a piece of equipment made from higher quality materials and costs $3,000-$4,000.

Commercial Smith machines don’t always have Olympic-quality bars, but they fit 2″ diameter Olympic plates. And they usually have ball bearings and a counterbalance to reduce the starting weight to 30 lbs or less.

The table below shows the bar weight of a residential Smith machine compared to various commercial Smith machines.

How To Measure Smith Machine Bar Weight

There are a couple of different ways to measure the weight of a Smith machine bar using a scale or a rope and weight. I’ll start with the scale method since it’s easier, and that’s how I did it.

Also, before you begin, it’s a good idea to talk to an employee at the gym, so they know what you’re up to. Don’t be a weirdo tying ropes to machines or stealing bathroom scales without asking… be a weirdo with permission. 😂

Option 1: Scale

First, find a box or sturdy object you can use to hold the bar up off the safety stops at the bottom of the machine. Then put a scale on top of the box and let the bar rest on top of it. The readout on the scale will indicate the weight of the bar.

If you don’t have a box, you could put the scale on the floor, step on the scale while holding the bar, and record the weight. Then weigh yourself without the bar and subtract that from the first measurement.

Option 2: Rope & Weight

For this measurement, you’ll need a thin rope about 10 feet long and a series of 10, 5, and 2.5 lbs weight plates. Tie one end of a rope around the middle of the bar, Then throw the other end over the top crossbar of the machine.

Now move the bar up to one of the top hooks, so the loose end of the rope is on the floor. On this end, tie some weight plates. Next, unhook the bar and see if it balances.

Add or remove weights until the bar is in near-perfect balance. When the bar is balanced, the weight tied to the rope equals the bar’s weight.

Why The Weight Of The Bar Is Important

Admittedly, that’s a lot of work to find the weight of a Smith machine bar. So why does it matter in the first place?

For one, it helps you make more accurate percentage-based adjustments to your weekly weights lifted on Smith machine exercises. And the incremental increase is an integral part of any progressive overload plan.

Also, knowing the actual weight of the bar helps determine your starting weight based on a similar free-weight exercise. For example, if you normally bench press 135 lbs, you may want to add a 10 lb plate on each side for the Smith machine bench press.

Keep in mind this is not always a perfect comparison since the path of the Smith machine recruits different muscles.

Now that I’ve answered the question “how much does a Smith machine bar weigh?”, you can better understand how much weight you’re actually lifting when using this equipment.

While being off by a few pounds won’t make or break your fitness results, those who pay attention to the details tend to get results faster.

So if you’re the type who likes to get detailed answers to your fitness questions, check out some of my other related articles below.

Other Bar Weights & Machine Weights

How Much Does a Curl Bar Weigh?

How Much Does a Leg Press Weigh?

How Much Does a Hex Bar Weigh?

How Much Does a Deadlift Bar Weigh?

Plus, check out my other great content on all things fitness related. You will find answers to all your questions about exercise, supplements, and nutrition.