Here’s how you determine what length of barbell you need!
For a Bench Press Rack
First, if you already have a bench with attached bar holders like in the image on the right, measure it. What you want to measure is the outside width of the rack. Be sure to measure from the outside of one side to the outside of the other, not just the inside distance.
The reason for this is the inside collars of the barbell (that you slide weight plates up against) needs to be farther apart than this measurement, so that the collars are sitting on the outside of both posts. This makes it so there is no interference when you rack the bar and when you load and unload plates. So the full space between the posts is therefore available to you to grip, depending on your preference of grip width.
As of writing, all of our benches are olympic width. What this means is the above measurement is going to be about 48″ wide on all of them. To fit it, you generally need a 7ft bar. A 7ft bar will always be long enough that collars will sit outside the rack. To be specific, you will have about 51-52″ of shaft on the bar, leaving a couple inches of slop in either direction so that you don’t have to worry about racking it perfectly in the center. Two inches of slop is just right. But less than an inch requires a lot of precision can can result in some nasty mishaps. You certainly don’t want to have trouble racking the bar after a heavy set where you barely completed the last rep of bench presses and need to rack the bar quickly.
Back in the day, bench press units were made like the above, where the bar holders were so narrow you would grip the bar outside the holders instead of between them. Any serious units today are not narrow like that. You can still find narrow ones like this, but they are the cheap variety in sporting goods stores that you should not be buying.
For a Power Rack or Squat Rack
Virtually all power racks and squat racks (half racks) made in the last 20 years are olympic width to fit a 7ft bar, or about 48″ (4ft). There’s almost no need to measure it.
The key for most setups is to make sure the bar has at least a 51″ shaft between the inside collars. That way you can be sure it will fit on any power rack.
For Independent Squat Stands
Independent squat stands are 2-piece semi-portable designs that you adjust to whatever distance apart you want. They are a different matter. The best way to use these is set them to olympic width just like a squat rack and use a 7ft bar. You’ll have to measure the distance and put markers on the floor.
However, you can set these to any distance apart you want. Be careful that they don’t get in the way of your feet if you’re squatting off them. As you can see in the pic above, they can get in the way pretty easily, even at olympic width apart.
Women’s Olympic Lifting
Olympic lifting is a different thing than “olympic width” racks. Olympic lifting refers to the snatch and the clean-and-jerk, both done by lifting off the floor and not a rack.
Men’s olympic lifting bars are 7ft, just like most bars.
Women’s olympic lifting bars are around 6ft to 6.5ft. The grip length of the shaft is exactly the same as a men’s bar. They make the sleeves up to 6″ shorter, so you won’t be able to fit as much weight on them. Normally that’s still plenty of space on the sleeves.
Other 6ft and 5ft “Shortie” Bars
Other bars that are not women’s bars are made 5ft or 6ft long for no other reason than they are cheap accessory bars. They aren’t meant for heavy lifting, just things like curls and other light work you can do by picking it up off the floor, without the need for a a rack. These don’t have the same 52″ inside grip length as 7ft bars and 6ft women’s bars and will not fit on a power rack. The grip length might only be 40″ or so.
There are some exceptions. “Rackable” 6ft bars will fit on a power rack because they are made similarly to women’s bars but with a larger shaft diameter such as 28mm or 30mm, instead of the women’s diameter of 25mm for their smaller hands.