Last Updated on 15 July 2025 by Maelle
Here’s the situation: You’re standing on your couch with a hammer and nail in one hand and a level in the other. You’re trying to hang a series of framed pictures, but you want them to hang in a straight line—after all, this isn’t some kind of over-the-couch gallery featuring the Leaning Tower of Pisa. The problem is, it’s physically impossible for you to hold the level against the wall while hammering in a bunch of nails. You’d need an extra arm to accomplish such a task, and you don’t have one. If only the level could hold itself against the wall, and you could hammer in the nails with both hands free.
Guess what? If you had a laser level in your toolbox, that wish would come true. A laser level projects a visible, perfectly straight line on a surface like a wall or floor. Since many laser levels mount to a tripod or even the wall, you have both hands free to hammer in nails or align tiles. A laser level simplifies DIY projects such as hanging wallpaper, tiling a kitchen backsplash, installing a long shelf or cabinet, or building a deck.
You might think that since the tool has the word “laser” on it, it’s an expensive addition to your collection. But laser levels are actually quite inexpensive. You can buy a simple model for as little as $20.
Laser levels are found in the construction, cabinetry, and civil engineering industries, and are commonly used for concrete and asphalt work. Grading, landscaping, and surveying companies also rely on laser leveling systems. Framers use laser levels to check the alignment of openings such as windows, doors, dormers, and skylights.
If experts use these tools, why not try a laser level?
Laser Level Technology
Laser levels use a laser, an amplified and focused beam of light emitted by a semiconductor device called a diode. These light-emitting diodes, also called LEDs, are found in many common devices, including digital clocks, remote controls, and television screens.
To understand how a laser works, it’s helpful to know that the word is actually an acronym for Light Amplification by the Stimulated Emission of Radiation. Simply put, when certain electrons are stimulated, they emit a beam of light. When mirrors or prisms collect this light and direct it in one direction, a laser beam is produced.
Laser levels project a beam of light that can be used as a visual chalk line when a straight, level reference point is needed. The size of the beam of light depends on the size of the diode. In this case, smaller is better: a smaller beam of light is more accurate. With a wider beam, the actual “level” point can be located anywhere within the beam’s width.
Early laser levels were limited to indoor use because the laser light wasn’t bright enough to be seen outdoors. Today, more powerful laser levels can be used indoors or outdoors, and many are designed to be used with a light detector that “reads” the laser light. These devices are positioned away from the laser diode, then moved up or down until the projection is detected and signaled in response by a beep or flash.
Most lasers emit a beam of red light. Some manufacturers now offer green lasers that are 400% brighter than red laser beams, making them more visible for indoor applications. However, the technology required to project green light requires more energy than red light, so battery life isn’t as long. Red lasers are generally more accurate and reliable over a range of temperatures.
Laser levels are typically made with small, low-intensity diodes and are powered by rechargeable or alkaline batteries. As with any laser, looking directly into the light can be hazardous to the user’s eyes, so wearing safety glasses is always recommended. The light from a laser level should not be directed at another person. Now that you know how these lasers work, let’s learn how to use them. How to Use a Laser Level Laser levels are easy to use, and thanks to the variety of models available, there’s a style to suit every application. Different types of laser levels have been developed for specific uses, but all laser levels have two common components: the laser and a leveling base that can be placed on the floor, mounted on a wall, or attached to a tripod. This base helps project the light at the required height. There’s also a leveling mechanism, either a bubble vial, a pendulum and magnets, or electronic sensors (the differences between these two types of mechanisms will be discussed later). The housing is usually made of durable plastic or metal, sturdy enough to be used on a construction site.
Laser levels find “level” in a variety of ways. Manual laser levels work in the traditional way: The user aligns a bubble inside a vial by repositioning the level or turning a knob. Well-suited for typical DIY projects, these laser levels are less expensive and require fewer batteries than a self-leveling device.
Self-leveling devices offer a greater degree of accuracy. They work best when placed on a surface the user determines is “near level.” You can use a bubble vial to manually level the device before the device’s self-leveling mechanism takes over. The laser component hangs like a pendulum inside the level. Magnets and gravity work together to hold the pendulum still, and the beam is then projected through a light or prism. Some laser levels are equipped with electronic self-leveling sensors that improve accuracy and reliability, making them ideal for busy outdoor jobsites. For indoor work where the level is frequently moved, a self-leveling mechanism saves time and increases reliability.
Types of Laser Levels There are several types of laser levels, varying in use and cost: learn how to buy a professional laser level: A dot generator is the simplest type of laser level. It’s essentially a spirit level that projects a laser point and sometimes incorporates a line generator that can be folded in front of the beam.
Dot lasers project a single point that can be level, square, or plumb. There are a wide variety of models ranging in price from $20 to over $500. While the least expensive models are best suited for indoor use,
other models can be used outdoors.
A line laser is a point-to-point level that can shoot multiple horizontal and vertical laser lines using multiple LEDs over a distance of 65 to 100 feet (19.8 to 30.5 meters). Designed for indoor use, they often feature up-plumb and down-plumb functions. Some models now include pulsed light technology that works with a light sensor, so they can be used outdoors or in bright interior spaces. Prices range from $40 to over $600. Rotary lasers project a rotating dot to create a 360-degree line. A detector is used to read the laser lines over a long distance. Most rotary lasers also feature single-line generators and up-and-down plumb capabilities. Ideal for outdoor work, such as road grading, laying foundations, or pipe laying, these laser levels are the most accurate and expensive, ranging from $250 to over $2,000. Manual and automatic leveling options are available, and they can be operated by remote control. Some rotary levels, designed for grading or foundation work, are so large that they must be mounted on a platform or tractor. Thanks to the advancements in its technology over the past decade, the laser level has become more accurate, smaller, easier to use, and more affordable. While once used only on large construction sites, contractors large and small are now finding that laser levels can turn a two- or three-person job into a one-person job. Today’s laser levels allow engineers or contractors to draw up a building or site design faster and more accurately than ever before, with less effort. In some industries, such as aircraft and shipbuilding, lasers provide real-time feedback by comparing the plan to actual CAE/CAD files, and it’s very likely that the same technologies will soon be available for large construction projects and home building.
Some laser levels even feature Bluetooth wireless technology to transmit their dimensions to a handheld computer, providing site-specific information on-site. As laser technology improves, its advantages will translate into additional features for levels. Self-leveling models and remote control options will continue to develop and improve. And as prices continue to drop, laser levels of all types will find their way into more and more toolboxes.
