Sizing Up Bosch Laser Measuring Tools – Time To Ditch The Tape Measure?

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laser measuring

Since I often work alone, I’m always looking for anything that can make my workday easier. And no, that doesn’t make me lazy – that makes me efficient and more productive. (That’s my story and I’m sticking to it!) One thing that’s frequently tough to do solo is to get accurate measurements over long distances or in tricky spaces. Many is the time I’ve balanced on a ladder with the tape measure extended out, only to have it buckle just as I’m trying to read it. Today’s laser measuring tools are super-accurate, reasonably priced, simple to use, feature-packed – and they don’t buckle. We’ll give you an overview of Bosch’s line of laser measuring tools, and take a closer look at a couple of them.

Laser measuring tools can be a huge time and frustration saver, and today’s crop of laser measuring tools offers something for everyone, from apprentices to engineers. Whether you just want to measure a straight line from point A to point B, or you want to take multi-surface measurements and upload them via Bluetooth to your mobile device, there’s an option aimed at you. Bosch’s GLM line of laser measuring tools includes the GLM 15, 30, 35, 40, 50, 80, and the high-tech 100C. The number indicates the distance in meters that the unit can measure accurately, from 15 meters (approximately 50’) for the GLM 15, to 100 meters, or 330’, for the GLM 100C. Bosch sent us an assortment of most of the models for this review and comparison.

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Part of the Bosch GLM lineup…

Laser Measuring 101

Many users don’t need all the fancy-schmancy added features; they just want something that’s fast, easy and accurate. Marc took a look at Bosch’s basic laser measuring tool, the GLM 15, and was suckered into volunteered to share his insights with us!

Bosch keeps it simple (and user-friendly) with a one-button design on the GLM 15
Bosch keeps it simple (and user-friendly) with a one-button design on the GLM 15

I have been using the GLM 15 for over a year now. As a real estate agent, I frequently need to measure room sizes prior to putting a listing on the market (that’s why we get paid the big bucks. . . room measuring)! It’s also super glamorous work. Measuring rooms is a task I’m typically doing solo. The GLM 15, and laser tools in general are ideal for this type of application. What used to be an awkward dance of hooking the tape on a corner or laying down a tape and attempting to back yourself to the next wall without disturbing the precarious alignment of the tape has been replaced by a quick button push. Measurement is nearly instant – just butt the laser to one wall and fire it at the opposite wall. Voila!

One weakness for what I would describe as the majority of laser users is the complexity of almost all laser distance measurement options on the market. This is where the GLM 15 really excels. It has one button, and pushing that button is really all you need to know. Push it once for continuous measurement, push it again to hold the measurement. Boom! You’re done! No need to contemplate the Pythagorean Theorem, figure out which sequence of buttons you need to press to calculate room volume, or get flashbacks to highschool geometry class while taking multiple angle measurements. It’s a simple tool for simple, dead fast measurements. It’s small enough to carry in a pocket, which I frequently do when showing homes to clients. I’ve had clients wonder how high a ceiling is, whether a wall was long enough to accommodate their furniture, and even how deep a pool is (not sure how accurate that last one was, but it appeared to work). These answers were all provided briskly without any measuring tape clunkiness.

If most of the measuring you do involves cutting lumber to length, well, laser tech just isn’t quite as handy as your tape measure. For guys and gals measuring rooms, estimating jobs, and calculating a quick wall length, the GLM 15 is a rockstar. Two AAA batteries go a long way with this unit, and they make it easy to swap out batteries. The only thing I’d really like to see in the GLM 15 is a backlit display – it can be very difficult to read in dim environments. Other than that, it’s hard to go wrong for a great laser distance measure at around $40. However, if you’re wanting a backlight, longer distance capabilities, or some of those more complicated calculations, that’s where a few other models step in. Phil will be taking the reins again for here on out. Take it away Phil!
– Marc

The Bosch GLM 40 Laser Measuring Tool

A little further up the laser measuring food chain, we find the GLM 35 and GLM 40. They look identical, and many of the differences between the two are minor. The GLM 35 has a useful range of 120’ vs. 135’ for the GLM 40. Both offer continuous measurement, and have the ability to measure length and distance. They can also calculate area and volume, and perform addition and subtraction. Both models also include a backlight, for increased visibility in low-light conditions.

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The backlit screen on the Bosch GLM 40 helps in dim light

What does continuous measurement mean? Activate the laser and watch the measurements move in real time as you move closer or farther from the target, just like a tape measure. Hold the measurement by pressing the measure button again.

Sizing Up The Bosch GLM 40

So aside from measuring out an extra fifteen feet, what is the GLM 40 doing to make it worth an extra thirteen bucks (current prices are $79 for the GLM 35, $92 for the GLM 40 at Amazon)?? It has a 10-measurement memory, and comes with some useful accessories – a canvas case, a skinny little lanyard, and some laser targets.

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The Bosch GLM 40 with case and target cards

The case is a good idea, even if you don’t plan to carry it on your belt often; it serves as protection in case it gets dropped (a likely scenario – for me, anyhow), and helps keep it clean. Here’s a quick look at the GLM 40 from Bosch:

The 10-measurement memory could be a handy feature. Much of my time is spent working on old houses, which tend to have a lot of character. Character, in old-house-ese, is defined as the absence of straight, plumb, level and square surfaces. Often, when building an interior stud wall in place, no two studs are the same length. With the Bosch GLM 40 laser measuring tool, I could simply install my top and bottom plates, mark out my stud locations, and move from one to the next, shooting measurements as I go. The tool will store ten of them, in order, and my studs should fit nicely.

By the way, taking inside measurements like that is one of the most useful capabilities of a laser measuring tool, for me anyhow. It’s hard to get a precise reading with a tape measure, because normally the tape is bent at one end of the space being measured, and there’s a little guesswork. The laser, on the other hand, sits on one surface and beams its little electrons right to the other surface, giving you an exact measurement. I used this recently while installing a window header, and got perfectly sized studs. It would also work nicely for finish carpenters installing crown molding, for instance.

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Laser measuring is great for inside dimensions. Set it on one surface…
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The dot marks the spot…
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And you end up with a precise inside measurement

For the math-challenged – you can’t see it, but my hand is up – the ability of the GLM 40 to automatically calculate area and volume is a great feature. I can do fine when the room is 10’ x 12’. It gets a little iffier when it’s 17’ 11-¾” x 26’ 5-½”. This is great for estimating the amount of flooring, paint, or whatever, will be needed. As for volume, I doubt I’d ever need it, but HVAC workers trying to size a furnace sure would.

I took the Bosch GLM 40 outside, to get it some fresh air and some new challenges. For the laser measuring system to work, the laser has to have a surface to reflect off of. Often, there is no surface available where you need one, as in the case of measuring across the front of a building. This is where the target cards can come in handy. They have an adhesive strip with a peel-off covering, which can be stuck pretty much anywhere.

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A tricky spot to measure
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Think of the target card as your cheap labor. Peel off the backing…
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And stick it on the trim. Now just point and shoot.

I stuck it on the corner of our house, making sure to leave a small line-of-sight through the bushes. Standing at the other corner, I was able to shoot the beam through and onto the target card, and get a perfect measurement. This would have been a challenge to measure with a tape, especially if I had been doing it alone. It was almost 36’, so a long tape would be required. Then the tape would have to be threaded through the bushes, all without unhooking it from the corner.

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A precise measurement, without tramping through the wet bushes!

Another very useful feature of the Bosch GLM 40, which is not advertised, is the ability to take indirect measurements. Sometimes, you can’t take a direct measurement because something is in the way, or there’s no surface to reflect the laser – no overhanging soffit on a building, for example. To use this feature, there must be a right angle between sought distance (height) and the horizontal distance (depth). Pressing the Function button until the triangle appears activates the Indirect Measuring feature.

First press the Measure button to measure the depth, then aim the laser diagonally at the top point of your desired measurement (the top edge of the building, for example), and press the Measure button again. The tool shows your initial two measurements, and automatically calculates the third leg of the triangle – the height.

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Indirect laser measuring is a VERY handy feature.

How Accurate ARE Those Laser Measuring Tools?

If your laser measure isn’t accurate, it doesn’t really matter how easy it is to use. I checked the Bosch GLM 40 for both accuracy and repeatability, to see if it would give the same reading when measuring the same distance several times. Keep in mind that the accuracy of the laser measure, just like that of a tape measure, is totally dependent on the user measuring to and from the right spot.

To measure distance, I used a tape measure on the floor, with the blade extended to a baseboard 18’ away. I set the laser measure next to it, and lined it up with the 18’ mark on the tape. Actually, the laser was just a fraction past the 18’ mark, and that’s the exact reading it gave.

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Accuracy is key, and the Bosch nailed it.

To check for repeatability, I set the laser measure on the floor against a baseboard, and aimed it at the baseboard on the opposite side of the hall. After taking six measurements, they were all dead-on the same – 6’ 1-7/16”.

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Thank you, sir, may I have another…

Laser Measuring On Steroids – The Bosch GLM 100C

If you’re a high-end user – a construction manager, architect, or engineer, for example – you may want even MORE capabilities. The Bosch GLM 100 C offers 10 measurement modes: length, area, volume, angle, minimum/maximum length, continuous measurement, single indirect height, single indirect length, combined indirect height, and multi-surface. It also offers the accuracy of laser measurement with the added advantages of Bluetooth technology, allowing users to make accurate measurements that can be instantly transferred to smart devices via the free Bosch Measure&document and FloorPlan mobile app.

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The Bosch GLM 100C, chatting with its buddy…

According to Bosch, users can send information directly to a PC, tablet PC or smartphone (iPhone, iPad or Android device) – quickly, easily and without transfer errors. Simply take a photo of the jobsite using the Bosch GLM 100C measurement camera app, and then enter the distance into the photo. Perform the desired measurement and have it displayed directly in the picture.

The Bosch GLM 100C comes with a rechargeable Lithium battery, and features a precise, class-II laser. It can measure up to 330’ with 1/16” accuracy, has tilt-screen and touch-screen technology, and can do your taxes in four minutes flat. Okay, I made that up; it actually takes five minutes. This baby is for the serious power user; if that’s you, get the rest of the lowdown here.

Ready To Trash The Tape Measure? Hold Up A Sec…

So is everything sunshine and lollipops in Laser Land? While laser-measuring devices are extremely useful tools, there are some limitations. One of the most obvious is that they won’t work for very short measurements. The tool itself is 4” long, and it measures from the back end of the tool. The Bosch GLM 40 doesn’t register a distance shorter than one inch away from it, so the minimum it can measure is 5”. This limitation would apply to any laser measuring tool.

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For anything under 5″, grab the old tape measure…

There are many instances where it will be faster and easier to just use your trusty old tape measure. When there’s a big stack of 2 x 4’s to cut to length, the old-school way is to just hook the tape over the end and mark off your measurement. With a laser measuring tool, you’d have to stick a target on the end of each stud, or make sure the end is tight up against a flat, reflective surface, before shooting a measurement and trying to read the small screen on the tool. The same principle applies if you’re trying to find inside measurements, for example to make a cutout on a piece of plywood subfloor before laying it down around a toilet flange. Sometimes, it’s just faster and more efficient to grab the tape.

Pretty much all laser measuring tools are designed primarily for indoor use. They can be used outside, but it can be very difficult to see the red dot, particularly on bright days. It was overcast when I used it, and I still had trouble locating the dot sometimes. There are laser enhancement glasses available, which supposedly can help. According to Bosch, using the targets also helps to intensify the laser light.

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The target cards can help you spot the dot.

The backlit screen is great – it makes the measurements much easier to read, especially in dim light. A small quibble: The screen has to be at the right angle to be readable; if the top is tilted up too much, the display disappears. You can tip it down as far as you want, and it’s still readable. Also, the backlight dims after about 10 seconds, and goes out after about 30 seconds. This is normally plenty of time to check your readings, but I wish there was a way to get the light back on without activating the laser.

The only other complaint I have is with the size of the fractions in the display. The primary measurements are fine, very easy to read. The fractions, on the other hand, are so tiny that I missed them entirely on the first few readings I took. Part of this may be related to the fact that I’m an old guy with crappy eyesight, but I’ll wager I’m not the only one…I realize this is a compact tool, and the display area is fairly small, but it appears there is enough room that the measurement readings could have been shifted a bit to the left, so the fractions could be legible. End of old guy rant.

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Tiny fractions are tough on old-guy eyes…

Do You Need A Laser Measuring Device? Yes, You Do.

All of the Bosch units are extremely accurate. The GLM 15 is accurate to within 1/8”, and the rest are even more precise – to within 1/16”. The units are compact and lightweight, easy to drop into a shirt pocket or purse, or clip onto your belt. For anyone who has to make long, awkward, or frequent measurements while working without a helper, this tool would likely be a VERY welcome addition.

Aside from the obvious customers, like anyone in the building trades, these laser measuring tools would be a huge time saver for real estate professionals (and Marc), insurance adjustors, home inspectors, DIYers…Let’s just make this simple: If you do any measuring at all, get one. The GLM 15 is only $47, and heck, a good tape measure will cost $20, and it’s got nowhere NEAR the cool factor! The Bosch GLM series of laser measurement devices are widely available, and come with a two-year warranty.

laser measuring

Bosch GLM 15 $40

Buy Now - via Amazon

Bosch GLM 35 $79

Buy Now - via Amazon

Bosch GLM40

Buy Now - via Amazon

Bosch GLM 100C $214

Buy Now - via Amazon

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About Phil

Phil’s path to the pinnacle of success as HomeFixated’s Senior Writer was long and twisted. At various stages of his life, he worked as a framing carpenter, attended motorcycle mechanics school, served as an Army MP, did a hot and itchy stint installing insulation in Phoenix, owned and operated a small contracting firm doing residential renovations, and worked as an employee of a major airline (Motto: We’re not happy ‘til YOU’RE not happy). He is currently semi-retired, but continues to take on little projects, such as the total renovation of an old farmhouse. Yes, he is a slow learner. Future projects include a teardown restoration of his 1965 BMW motorcycle, and designing and building a kick-ass playhouse for his grandsons. Phil loves spending time outdoors, hanging out with family and friends, cool tools, and a cold IPA when beer o'clock rolls around.

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7 thoughts on “Sizing Up Bosch Laser Measuring Tools – Time To Ditch The Tape Measure?”

    • Unfortunately, James, Bosch doesn’t seem to offer the yellow targets anymore. They have a newer version, shown on the Bosch website, and there’s a “Buy now” link that will show you stores in your area. Home Depot also carries laser target cards, and so does Amazon. Do an online search for “laser level target card” and you’ll get several other options. Good luck!

  1. If you like these laser measures, you should check out the new Bosch GLM 50 C (& GLM 50 CX). It has an amazing color display and large numeric readout. Plus it has Bluetooth functionality that connects to the free Bosch apps.

    • Wow – now THAT’S the kind of display my old-guy eyes need! It has some other nice feature upgrades, too. The ability to measure from the front, center or rear of the unit gives you great flexibility. It has a threaded hole so it can be used on a tripod, and it works as a level, too. Definitely a sweet tool – thanks for the heads-up, Steve!

  2. These tools are great. As an Architect, and now GC, I purchased a Bosch Laser tape measure (I think it’s something like the GRM 225…not made any more but closest to the GLM 80) a good 4-5 years ago at least. I have checked the accuracy on numerous occasions against a tape measure (usually every other time I use it) and continue to get 1/16″ accuracy all the time. There are some limitations, but nothing beats the speed and accuracy, especially if you are on your own taking measurements for initial drawings and estimating. The backlight on the newer models is a very nice feature. I have to say, I’ve rarely, if ever, used some of the more advanced features for area and triangulation, but they can be very helpful to have…as long as you can remember how to use them. I do have to say that the size of the fractions (having seen one of the newer models here in action also) are incredibly small. My eyes, while certainly not Fighter Jet Pilot level, are not terrible and I had a great amount of difficulty reading the fractions. It would probably help if the display could be limited to 1/16ths also, instead of 1/32nd’s which is very difficult to see. That said, I would highly recommend the Bosch line of laser tapes. Mine has seen many years of use now and it has proved to be a rugged, durable and dependable tool in my arsenal. I never go to measure a site without it!

    • I agree that accuracy to 1/32″ is probably overkill for most users, but if the product can do it, no harm in providing it. A reading in 16ths is the same size as one in 32nds, and for cabinetmakers custom-building snazzy inset cabinets, or trim carpenters wanting their crown mould as accurate as possible, the precise readings could be a big help. Most of the carpentry work I do is framing, where boards can be “persuaded” into position, if necessary. I find that the added measuring precision helps me to cut my stock so it fits nice and snug, and it darn sure makes solo measuring a less painful experience. It’s become one of the tools I schlep along to every job – it’s so small, it doesn’t take up any room, and you never know when you might have to make a REALLY precise measurement…


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