At a glance, a level is a simple tool, yet when you do a quick search for the best available, you discover hundreds of choices. We at BestReviews have looked at all the variations so we can help you spot which features are important and which are just for show. We’ve also focused on a few favorites that underline the main differences.
Our top pick is a pair of box beam levels from Stabila, a brand known for precision. They cost a bit more, but these are professional standard tools of exceptional quality. To learn more, keep reading.
The heart of a level is a vial containing an air bubble suspended in liquid — usually colored ethanol. As the vial tips, the bubble moves left or right. There are two lines around the vial, and when the bubble sits exactly between them, it’s level. Build several of those vials into some kind of beam, and you have a tool for quickly and accurately measuring not just horizontal and vertical surfaces, but also angles. Thirty- and 45-degree options are common, and some have rotating vials which go anywhere from zero to 180 degrees.
The beam portion of lower-quality levels is usually molded plastic. Unfortunately, they’re rarely accurate. Aluminum is used for most tools. It’s light but strong and doesn’t rust, so the important surfaces you rest against the workpiece don’t get pitted over time. The aluminum is usually formed into a hollow box section, or an I-Beam, both of which resist flexing, which would affect results. This rigidity is particularly important on levels 36 inches and longer.
On lower-quality levels, the markings on the vial can be thick painted lines which obscure part of the bubble and lead to minor inaccuracies. On high-quality models, they’re thin metal bands, thus offering greater precision.
Some levels are sold with “certified accuracy.” The certification is done by the manufacturer, so you have to trust them to some extent, but claims are frequently supported by a lifetime warranty. Precision can be as high as plus or minus 1/32-inch over a six-foot length.
Vials come in various colors. It makes no difference to the accuracy of the level, but the human eye sees green more clearly than anything else.
Some levels have a magnet built in, which is useful if you’re working with steel or other ferrous surfaces. Strength can vary. If it’s important, rare earth magnets offer maximum grip.
Measuring scales may be included, in inches, metric, or both. How sharp these are affects accuracy.
With longer levels, it’s useful to have hand holds. A hole at one end for hanging it up is also convenient.
Rubber or plastic ends offer some protection if the level is dropped. Better ones are removable so you can slide the end of the tool tight against a corner when marking out, for example.
A padded case is nice, but something usually found only with premium tools.
You can find low-quality levels for just a couple of bucks. However, there’s little point in wasting money on them when a decent tool can be yours for just $20 to $30. If you rely on one for work all day, every day, you may want to invest more. The best builder’s levels can be over $100.
A. It depends. A few levels have calibration screws so you can make small adjustments to make sure they’re always accurate. However, if they get bent, it’s almost impossible to straighten them and you’ll need a replacement.
A. There are lots of vials of different sizes available — but that’s not usually the problem. It all depends on how the level is made. Lower-quality models are sealed and can’t be taken apart to insert a replacement. I-beams and box levels, while often more expensive, frequently have vial sections that can be unscrewed.
Our take: High-quality pro-grade levels in 16- and 48-inch lengths cater to all situations.
What we like: Made from strong but light aluminum box section. Removable shock-absorbing end caps. Hairline indicators for precise readings. Accuracy guaranteed for life. Nice hand holds.
What we dislike: Expensive.
Where to buy: Sold by Amazon
Stanley Hand Tools 42-468 Level Composite 24"
Our take: A great all-around choice and excellent value — as long as you get a good one.
What we like: Durable and shock resistant. Includes measuring scale and is also carded.
What we dislike: Some users said this may be best only for smaller tasks such as hanging decor on the walls.
Where to buy: Sold by Amazon
Our take: Specifically designed to plumb and level posts — and does it well.
What we like: Good size vials give a quick and easy visual guide. Durable plastic body. Magnets or strap for fixing. Also useful for pipework.
What we dislike: Poor magnets and weak band, though that’s easily resolved with a better band. Occasionally, vials are flawed.
Where to buy: Sold by Amazon
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Bob Beacham writes for BestReviews. BestReviews has helped millions of consumers simplify their purchasing decisions, saving them time and money.
![Stanley Hand Tools 42-468 Level Composite 24"](http://cdn10.bestreviews.com/images/v4desktop/image-full-page-cb/stanley-hand-tools-42-468-level-composite-24-dfd696.jpg?p=w1228 "Stanley Hand Tools 42-468 Level Composite 24"")
