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Harbor Freight’s 6″ digital caliper is so cheap, it must be a great deal, right?

Well, we’ve found that its battery life is incredibly short, so if you only use it occasionally you’ll often find it dead.  And the accuracy isn’t up to snuff for demanding jobs — testing it against some gage blocks showed some ranges with no error but others with an error upwards of .04″!

On the plus side, you don’t have to worry about dropping them as you would with one of the $100+ calipers from Mitutoyo.

Ultimately I prefer the Mitutoyo for regular use, but what do you think:  Hot or Not?  Let us know in comments.

Digital Caliper [Harbor Freight]
Street Pricing [Google]
Via Amazon [What’s This?]


31 Responses to Hot or Not? Harbor Freight Digital Caliper

  1. KMR says:

    You guys must have had a defective caliper.

    We have a couple of these HF cheapies in the shop and they are dead-nuts as accurate as the Fowler one I have that was many times the price. I’ve also checked my HF unit against my Starrett standards and found that the HF caliper reads perfectly against the standard’s rated size.

    So these are definitely hot, it is usually the first measuring tool I grab when I have to measure something accurately that is dirty or in an area that may cause damage to more expensive tools.

  2. Coach James says:

    Hot! I can’t afford $100 plus for one of these, but I can part with $12 when I got it on sale. I’m not a machinist so a slight error is ok. For determining if I can turn my rotors or not, it is plenty close. Also, I just take the battery out when I’m not using it.

  3. Hot:

    The one I use regularly didn’t come from Harbor Freight, but I got it on Ebay. If it’s not the exact same model, it’s definitely a similar Chinese knockoff. I never would have bought one if I didn’t get it for under $20. I did buy one from HF as a spare when they were on sale for like $8 but haven’t used it yet because my first one works so well.

    I’ve never had a problem with any measurements I’ve taken with it — it’s definitely more accurate than me trying to read off the markings on a tape measure or even a precision rule.

    Battery life has been OK for me. I’ve replaced the batteries once in the 4 years I’ve had it.

  4. KMRshopPC says:

    Busy eating lunch and thought I’d check my HF caliper again with a bunch of stuff of known precise sizes:

    1″ Starrett Micrometer Standard: 0.9995″ reading
    2″ Starrett Micrometer Standard: 2.000″ reading
    3″ Starrett Micrometer Standard: 3.000″ reading

    Precision 3/8″ Steel Dowel (actual 0.3752″): 0.375″ reading
    Precision 1/4″ Steel Dowel (actual 0.2502″): 0.2505″ reading

    Bearing Grade 3/8″ Ball Bearing (actual 0.3749″): 0.375″ reading
    Bearing Grade 1/4″ Ball Bearing (actual 0.2500″): 0.2505″ reading

    The manufacturing tolerance on the dowels and ball bearing is +/- 0.0001″. I’ve double checked their diameters with my Mitutoyo mics just now as well.

    So there you have it, at least my HF 6″ digital caliper is accurate to better than 0.001″ against other known higher tolerance pieces.

    Pretty good for a $16 tool!

  5. KMRshopPC says:

    Also, I’m we’re Energizer 357 batteries in these calipers… They’re availabe in 3packs. So you always have a spare (or two). I’ve probably had this Energizer 357 in there for at least a year. If I recall, I picked this battery because of its extended use ability.


  6. ABoyAndHisJeep says:

    Hot! I am an avid hobbiest and fix-it guy, these are extremely accurate for general as well as precise usage. My Grandfather who was a tool and die maker was amazed when he checked them out and I told him how much I paid at HF!

  7. Chaim says:

    HOT. I have one and it’s dead on. I’ve not had a problem with the battery life.

  8. Stan says:

    Had mine for several years. Seems pretty accurate. Mine looks similar, but does inches in fractions and decimals. Not a machinist, but woodworker so anything over 1/64th in accuracy is an over kill

  9. Grimshot says:


    For $16.00 it saved me some bucks determining my very old Raleigh bike had a 15.2 cm not a 16 cm seat post….

  10. Toolaremia says:

    Hot. Mine had proven very accurate. Checked against feeler gauges and an expensive caliper, and it’s right on. I generally only need “hairy eyeball” close. Heck, wasn’t so long ago I worked at a manufacturer so poor I would measure hundredths with a steel ruler and my eyeball! I would have killed for a $16 caliper.

    Also been fully hacked for data collection:

  11. Lungofish says:


    Somewhere online (can’t find it at the moment) there was a guy that figured out the battery thing – they’re basically always ‘on’ and the on/off button only turned off the lcd, saving only a small percentage of the total power draw.

  12. Remarksman says:

    Hot! I’m happy with mine, but I don’t need super accuracy. The comment about the battery life is right on, though. Seems to fade very quickly.

  13. Frank Townend says:

    Hot in my shop too. I use it all the time, the first battery lasted forever and I get nice consistent (and accurate) readings.

  14. Pencilneck says:

    Hot, I’ve got one I’ve been using for a while, I just zero it out often and it does fine. Battery life seems to be pretty good as well, it turns off after a while. Well worth the purchase to have a back up or use out in the field.

  15. Ffaelan Condragh says:

    NOT. used one when milling down some MDF for a trade show gig. after the second pass through the planner the measurement was bigger than before it was the first pass.

  16. Dave says:

    Hot! Plenty accurate for everyday use and my battery has been good for a year so far. If you run into a job where it’s not accurate enough, hell, you’ve probably used them for a dozen or two other jobs in the meantime and got your money’s worth. If you need the extra precision, you are probably using tools or parts that are capable of that precision or better (otherwise you don’t need them!) … an upgrade on your caliper will probably be well worth it working with that kind of equipment or parts!

  17. Roman says:

    Hot! I have been using mine for 3 years now and it works like a charm. They are as accurate as any other pair I’ve used and they have withstood some short drops without harm.

  18. Aboxman says:

    My post was Nuked, so lets try again:


    Use one regularly for Quoting purposes (Close is good enough for what I do).
    Lungofish has it right, remove the battery after every use, and they will last a LONG time. See http://www.fliptronics.com/tip0006.html also, an SR44 is supposed to work better, but I’m still on the second of my original batteries after about 2.5 years of use.

  19. Steve Relaz says:

    I have one of these calipers as well and my battery life is terrible as well. I literally bought a 50 pack of batteries off ebay for the occasional time I use mine. I always find it dead. It does seem accurate but the battery life stinks. I hate to spend 100+ on a good one, but probably will some day. Maybe I can ebay my current one?

  20. jay says:


    Been using mine for about three years now, have dropped it quite a few times (one time in some nasty oil/grease) Have to zero it out every once in a while. I work in a ball manufacturing plant and from time to time I use these to “mic” a ball because it’s quicker than using my micrometer. I’ve had it for about 4 years and I probably have to replace the battery in it about once a year, the batteries that came with it didn’t have a long life but the ones I’ve put in since have lasted a good while. I always make sure and turn it off when I’m done with it – that may have something to do with them lasting so long. I think (at $16 it’s understandable) there may be some that calipers out there that eat batteries really quick and may be defective somehow.

    I even bought a pair of the even cheaper composite calipers from HF to use around the house, they don’t read as many decimals out but I think they were on sale for 8 like bucks so who cares! Like people said before, it beats the heck out of reading off of a tape measure. Give em a try, I’m sure you’ll like them.

  21. jay says:

    As you can see, when I really thought about it I realized I’ve had them for about 4 years, not 3 years – not sure where that 3 came from. Sorry 🙂

  22. Antony says:

    Hot and cold.

    I’ve got a Mitutoyo and a number of cheapies. Ironically if you use it a lot then the cheapies are just as good, accuracy generally within 1 count all up the scale on mine, and you’ll remember to replace the batteries which they HOWL through (actually last about 8 months). But if you don’t use it a lot, the battery is always dead when you need it, or worse just at that point between alive and dead where it looks fine but reading jumps up and down just enough to be believable but cause big errors. The Mitutoyos don’t have these problems, they use 1/4 the power when on, and actually turn off rather than just blanking the display like the cheapies (not that you need to).

    In fact the battery problem is so annoying I’ve got to the point where I just reach for the vernier Mitutoyo (the digimatic stays in the office where I won’t be tempted to use it as an adjustable spanner, which is always an option around here, in the same way as cheap micrometer = excellent G-clamp). There are also so many brands and they change so often it’s hard to keep track of which are best. But anything’s better than the plastic Mitutoyo that stopped working after a few weeks and was nowhere near as accurate as what you can get these days for almost nothing. Plus the plastic ones make terrible spanners.

  23. Noah H. says:

    Hot. I’m a machining student and the shop calipers are often abused beyond belief. Things often disappear from the shop right before your eyes. I’d much rather lose my $20 calipers than a very nice pair.
    The battery life is not an issue as long as you use name-brand batteries and store it properly. Whenever I left mine out of its case, I found it was still on. Never has that happened when I put it in the case. Buying cheap batteries off of ebay isn’t a good idea, because they have probably been sitting in a warehouse for many years and their nominal voltage will be below 1.44v before they even arrive at your door.

  24. ARBaker says:

    I am a maintenance mechanic for a closure manufacture for the beverage industry in California. I have bean using my set of harbour fright digital calipers for the last 12 years. now granted i don’t do very much mill or lathe work, but for bearing sizing and things of that nature during repairs and rebuilds of our equipment. the HF digital calipers have served me well. I have had some of our old machinist check em out and they were impressed with the quality for the price. I have used them for some small machining projects and have had no problems.

  25. GPMackler says:

    Hot! I use this to determine the seat post sizes for bicycle frames (27.2mm, 26.8mm) and dropout spacings (130mm, 126mm, 140mm). It always accurate. This tool would have been a screamin’ deal at twice the price. It beats trying to figure out the lines on a vernier caliper anyday and its accuracy is EASILY better than my errors when using a regular vernier caliper. I couldn’t recommend this tool more!

  26. tom hoo says:

    Have had one for many years and think it is HOT. It works just fine and when you need to pesky mm readings, it really pays for itself.

    However, I just bot another one (7/14/12) and I’m sad to say, the instant you pick it up, you can tell it has been massively cheapened. The surfaces are rougher and I swear softer. How this fits in with their “economy” digital line is beyond me. To think of something “cheaper” is scarey.

    I was able to show 2 digit error in the mm setting just closing them to zero if you move the carriage around when opened. I figure the first test is do they return to zero, right?

    At least I waited until they were on coupon sale for $9.99

    Oh well. I was going to get the 8″ if they went on super sale, but the most I’d pop for them is $12.

    I’d be interested to hear from other people who have recently purchased these calipers.


  27. Bob says:

    Not Hot or Cold, but rather:


    They work well enough but they eat batteries. I have 3 of the digital indicators and 2 of the digital calipers.

    I never use the digital calipers anymore… been years… because I use calipers daily and it was infuriating always changing batteries when I was in the middle of something with machines running or something time sensitive (something cooling or heating – glue or epoxy hardening…) though batteries are easy enough to change with that little door, and the case has a holder for the battery. So for a hobbyist who doesn’t use them often, maybe they’re not bad if you’re willing to pop the battery out after use. My Mitutoyo goes about two years of constant use on a battery and I am absent minded and leave it on for hours every day.

    As for the dial indicators… The accuracy is good enough, but they suck batteries like the plague… worse than the calipers. Again, that wouldn’t be so bad, but they don’t come with a case, and the batteries are inconvenient to replace. you have to pry up a little door made of soft plastic which deforms a bit every time you do so and the battery is held by a little plastic finger which will break at the slightest provocation. I’ve actually considered altering the door so I could pop batteries out between uses as I only use the jig in which they reside perhaps 50 or 60 times a year. But as it is, I change batteries (on all indicators in the jig) at least 3 times a year and always at an inconvenient times. The indicators seem to be able to predict when I don’t have spare batteries. On my list of “todo” this year is to upgrade to Mitutoyo for every gauge & indicator in the shop.

    So – are they accurate? Yes.
    Are they irritating as hell? Yes.

    Conclusion: “Warm”

    For a patient hobbyist with a lot of extra batteries, go for it. If you plan to use them to make a living… avoid them for all but the dirtiest uses where you know that the conditions will damage a good indicator / caliper.

  28. Bob Sherman says:

    Mine (PITTSBURGH 9.99 with coupon) is not accurate. Errors have been 5-15 thousandths in the range of measurement I’ve been using: about 0.4-1.3 inches.

  29. Eric says:

    Sometime in the last two years they did a revision update on the digital calipers at HF and knocked the quality down a lot. My older pairs seemed decent but these feel flimsier. Haven’t sat down and verified the actual measurement quality difference if any.

  30. Peter says:

    Mine would have a dead battery when I removed it from the case. The foam inside of the cover was pressing the power switch when the case was closed. I cut that small section of foam out, haven’t replaced the battery since. 6+ months of daily use later.

  31. Jim says:

    HOT! I have two of the HFT digital calipers. I use them for machining and many other things. I also have very $$$ Mitutoyo digital caliper. I find the HFT calipers to be excellent. Sure, the battery cover might pop off once in a while, but the tool is very accurate and I have no real preference when I reach for one. I think I paid $9 and $14 for them versus $120 for the Mitutoyo.

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