Johnson Laser Distance Measure Review

July 27, 2011 | by Ethan (email) |

When I talk to tool manufacturers, invariably they’ll ask me “How can we improve this __________ “, and I’ve learned one of the most popular answers to that question is “Add a laser.” You could be discussing anything from sharks to concrete cutters, and the answer is the same. So what’s better than a tape measure? A tape measure with a laser (which is sort of what a laser distance measurer is).

It was exciting when Johnson Level & Tool offered the chance to review their Laser Distance Measure (LDM), model #40-6001. LDMs are real useful for doing estimates, and I’d argue that every carpenter, painter, flooring contractor, deck installer, roofer, builder, etc. should have one in their tool box. Keep in mind, LDMs don’t replace the traditional tape measure as they both have different uses.

On a side note, if you ever do have feedback for manufacturers, I’m happy to pass that along. Constructive criticism is like a gold mine for product managers. It helps them to know what products people actually want and how to make the next generation models better.

Johnson LDM #40-6001 Overview

Johnson packed a strong feature set into a small form factor. With the 40-6001, you’ll find measurement memory, an integrated level for better accuracy and sound activation. All the expected measurement modes are included- length, area, volume, and indirect. The carry pouch, wrist strap and rubberized cover offer good protection, and I liked the LED backlight. Accurate to +- 1/16 of an inch, 165″ max distance is more than enough for most users but may not be enough for commercial contractors. Be sure to read through the manual and keep it in the carry pouch for future reference.

Johnson released this laser distance measurer exactly one year ago. You can see the press release if you don’t believe me. Since that time, competitors have integrated other features like angle measurement, and rechargeable batteries, and I’d expect to see that in the next model. I also think the addition of a few magnets like manufacturers have done with levels will make this tool even better for HVAC professional and plumbers.

Taking Measurements

Johnson sent the LDM a few months back, and I immediately started walking around the house checking the distance between me and everything else (like small children and various furniture). I used it for projects like estimating how much floor coating and drywall we’ll need in the new workshop. It was also dead useful to ensure we poured the concrete shed base in the right place. We wouldn’t want to accidentally end up in the easement or worse, a neighbors yard.

It took a bit to get comfortable with the symbols and how to move between the different measurement modes. Just about every button has two different functions. For instance, the button for sound activation doubles as the memory recall button. Other reviews have noted that the fractions are rather small, and I’d agree.

I found it was really easy to take measurements and calculate area and volume. The indirect measurement takes advantage of the Pythagorean theorem (flashback to high school Trig). Johnson provided three different ways to achieve an indirect measurement – single, double and triple. Just make sure you’re familiar with each. The manual fits nicely inside the carry pouch, and I’d recommend keeping it there for future reference.

But Wait! There’s more

Johnson included a couple other niceties like sound activation, a small integrated bubble vial to improve accuracy, memory for up to 10 measurements and an LED backlight. Stake out mode is useful for measuring repetitive distances, and the reference point can be set to front, tripod and rear.


I found the #40-6001 listed for about $150, which is on par with competitors’ products with similar specifications. I did find a comparable LDM for $130 and we’d expect a price in that ballpark when Johnson releases a new model.


  • Measure Range* 20” – 165’
  • Accuracy* ± 1/16”
  • Measure Speed* 0.5 seconds
  • Laser Type 650 nm, ± 10nm, Class II, ≤ 1mW
  • Power Supply 9V Alkaline Battery (included)
  • Battery Life 5000 measurements
  • Dimensions 4.1” x 2.4” x 1.3”
  • (104 x 61 x 33 mm)
  • Working Temperature 32°F to 104°F (0°C to +40°C)
  • Storage Temperature -4°F to 104°F (-20°C to +60°C)
  • Auto Shut-off Laser 30 seconds
  • Auto Shut-off Main Power 3 minutes
  • Sound Activated Noise Level Greater than 75 decibels
15 Responses
  1. My sister bought me a tape measure like this one (different brand though) several years ago and I use is at various times. Every time I use it with someone else around, they ask about it and tell me they are going to go get one.

    It is an excellent tool to have a a resource.

    Just my thoughts,


  2. paintergal says:

    So many useful tools. On a limited budget, however, I cannot justify spending the bucks on something that would be used occasionally. In a perfect world, I’d love to have one!

  3. Joe says:

    Good stuff, looks like a useful tool. Not sure I could ever justify one for myself.

    Also, sorry to geek out, but the Pythagorean Theorem is Trigonometry, not Calculus… resisting the urge to geek out more and explain.

    • Ethan says:

      Ah you got me- good catch there Joe. I’ve updated the post 🙂

      • Joe says:

        No big deal, as I said, I was being a geek, I would guess most readers wouldn’t have caught it or even cared.
        Looking at the manual it looks like they actually use the Pythagorean theorem, but I suspect that measurements will be a bit off (due to targets not actually making a right triangle). If they really wanted to make it more accurate (but probably more expensive) they could have included an accurate accelerometer to determine the angle of the device when it takes the measurement, and then do more complicated calculations using that angle. Then you could hit two arbitrary points and it could tell you the distance between them.

  4. jeff_williams says:

    I have this model also. It is indispensable for quick measurements. Every estimator should have one. Could be really useful for realtors too. I ditched the protective rubber cover on the first day.

  5. Great review Ethan. I don’t remember much trigonometry from HS, does it have a refresher course in that gadget?

    • Ethan says:

      After you get used to the display, it really does a good job of walking you through. For instance, when you want to use the double indirect mode. It has a little symbol of the measurements you’ll need and next step flashes.

  6. Very cool, I have some buddies who use some distance tools similar to that in the Fall when they are hunting. It make sense to me there would be the like tool for measuring distance on a different scale. Keeping up with tools and the changes they go through is very interesting. And you having the opportunity to see it all early and first hand are very lucky! Thanks for the info. Dave

  7. DIY Cabinets says:

    I’ve been using this kind of tool for years now, so handy!

  8. Eek565 says:

    This is one of those tools that I think is more useful for a tradesman than your average DIYer given the price point. Once the prices come down on laser devices, and I suspect they will soon, I’m sure I’ll be looking at adding one to my arsenal of tools.

    • I thought that at first too but it is amazingly useful. I use it on my friends projects as well as my own. With the right coupons it is really close to $100 at Home Depot.

  9. HANDYMAN51 says:

    Our realtor used a similar device to quickly measure room sizes. Very handy for use in that profession.

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