System units setup in 3ds Max

loocas | 3ds Max,technical | Wednesday, June 3rd, 2009

I can’t believe how many artists are actually confused and misuse the Units Setup dialog.

I hope to provide a definitive answer to using this dialog and properly setting up your system units in 3ds Max in this article, for good!

Units Setup Dialog
The dialog is super simple, you can find it under the Customize > Units Setup… menu, the first part only allows you to setup a visual representation or visual feedback of the used units, not the actual scale of them! It has nothing to do with how big your objects are in your scenes (relative to the units you wanted to setup, i.e. 100 != 100cm if your System units are set to Inches and vice versa), for fuck’s sake! Don’t you, guys, ever read anything that’s even remotely technical? I get it, you’re “artists”, but hell, if I get a new TV or a microwave or whatever, I open up the manual and give it at the very least a quick look!
Here’s how the thing looks, you can go for metric, US or custom units display. Hell, I setup my special “dub” units to show up in the sliders to give the arbitrary values a meaning, in this case a single “dub” equals to 100 meters.

System Units Setup Dialog
The second dialog, System Units Setup, is actually the most important one you should look into. There you’ll be able to actually influence the scale of your units so that a value of 1.0 equals to, let’s say, a 1.0 Inch, or a Centimeter, or whatever you set it to be!

Hell, you can keep everything in there on their respective defaults, you don’t even have to give a shit about the scale accuracy, or scale deviations, who cares, nobody wants you to have a MIT in Mathematics or Applied Physics, just one thing, look at the first line where it reads “1.0 Unit = [ ]”, does it say “1.0 Inches”? Yeah, I thought so, dumbass! This is where you need to specify how big you want your units (the friggin values in the sliders, spinners, whatever…) to be! So, if you live anywhere in Europe, for example, and you need to model in meters or centimeters for later scene assembly, making “cm” visible in your spinners just doesn’t do the job, specify the scale here and you’re done and I won’t yell at you over the phone why the fuck you animated the entire sequence, with particles, cameras, flying debris, animated materials etc… in Inches and not fucking centimeters, idiot!

Just to recap, for the slower ones, the first dialog to appear doesn’t change the scale representation of your system units, at all! It only allows you to show such units (or recalculate the values to – from) to the System Units you setup in the second dialog! That’s where the magic happens. Set it up the way your supervisor, TD or common sense, tells you to and you’re good to go!

EDIT (21-11-2010): You might find this post rather irritating or even smug, but please, take into account that this place is my own blog and I can write whatever I want here, second, it was a rant as I have more than enough experience with this issue in productions both, very small and rather large, and thus have the right to bitch about it and third, you’re not forced to read through if you don’t want to or can’t filter out the useful information. :)

I also welcome you to read some of my other posts that, and you can take my word on that, are written in a different tone.

Thanks for visiting and enjoy the rest of my site.


  1. loocas, couldn’t send you a message using the contact form, do you have any personal email or I should use Thanks

    Comment by Juan — June 22, 2012 @ 17:36

  2. Hey, Juan, sure thing:

    Comment by loocas — June 26, 2012 @ 22:30

  3. for fuck’s sake, finally someone who knows his shit!! I have been bamboozled by this for a long fuckin time, as models I have purchased are all over the shop as far as unit measurements go.
    Fuckin thanks fucking very fuckin much loocas.
    Q. If I buy a model in the wrong measurements will it fuck it up if I import it into a new scene with different measuremenets set up.? And fuck, if it does, is there a fuckin way ’round it…sake?

    I dig your laid back blogger style Loocas.

    Comment by Mal — August 20, 2012 @ 07:31

  4. Hey, Mal, thanks for the fucking comment, mate. :)

    As for your fucked up question. If you import the fucking thing with completely fucked up units into a different scene with proper units, the mesh will fucking get rescaled properly, but you’ll have to fucking fiddle around with it anyways as if the fucking units were fucked, I’ll bet my left nut the whole fucking thing won’t make shit of a sense anyways as it was most likely modeled by a fucking retarded monkey on crack.

    Hope this fucking helps. Cheers.

    Comment by loocas — August 21, 2012 @ 14:07

  5. This is so true. I´ve sunk counless hours into repairing files with incorrect units. It´s espcially annoying if the Geometry is rigged in some way.

    Comment by Sam — August 23, 2012 @ 14:16

  6. Hellow loocas , I respect your consistency and I agree, sometimes it needs to be hammered into people.. no big deal.

    Can you please clarify something, I’ll try my best to articulate this question:
    If I wanted to model a basic room in standard US feet and inches as a home builder would using a standard tap measure, (but I’m using decimals for inches) At the moment I’ve set….

    Grid spacing: = 0’1.0”
    Major Lines: = 12 (as a US tap measure has 12 inches per foot).
    – – – system units – – –
    1 unit = Inches
    – – – Display unit Scale – – –
    US standard Feet w/Decimal inches – Default Units: inches checked.

    Is this a good way to work when molding rooms for blue prints that an American architect might later use as a reference when building a physical building? I’m so use to modeling for games like Unreal, I’m not sure how things work in the real world of home building. Are my settings ok?

    I guess the reason I’m asking this is, since the default system units are set to feet, I’m assuming you wouldn’t get the detail if you needed to model objects in the room down to the inch level. Or is that ability predicated more of your grid snap settings and the system would still respect values smaller than one inch? In this case it would be better to leave one unit as feet and not inches?

    Advanced Thanks

    Comment by Mike — September 20, 2012 @ 01:24

  7. …Hello I meant, sorry about the typo

    Comment by Mike — September 20, 2012 @ 01:26

  8. Hahahaah this guy is great! you knwo more than 10 people asked him about this. lastly who do you set the units to milimimeters? >:)

    Comment by grabiel — September 27, 2012 @ 17:48

  9. The reason they are confused is because 3DS MAX is a lot more complex than you realise
    You only think the artists are stupid because you don’t understand the problem (and 3DS MAX) fully
    If you had taken the time to fully understand what the artists were asking OR FULLY SOLVED their problem you would realise this
    Two examples
    (a) changing the System Unit to a non-SI scale results in vertex data being stored in metric and a conversion factor being stored in the FBX header … this can result in strange behavior (so don’t do it)
    (b) the viewport clipping planes are dependent on System Unit … but are only configured correctly AFTER a reset
    You can prove (b) by creating a fresh scene with System Unit = 1 cm and then create a box size 0.001 mm … you will not be able to view it! Now set System Unit = 0.0000001 mm then RESET then create the small box … now you can view it as the clip planes are correct
    In general if you are angry – you must be confused. If you fully understand the problem and the artists then you would feel happy, not angry.

    Comment by Jack — November 10, 2012 @ 00:15

  10. Jack, thanks for your, rather interesting, input. However, I am no guru, but telling me I don’t understand 3ds Max is a bit offensive.

    Comment by loocas — November 27, 2012 @ 22:53

  11. Hi, I’m definitely a noob so please try to be patient with me….I am actually taking a 3ds Max class and am getting ready to submit my final scene with about 8 objects that I made. It is an outdoor scene and had the units set for meters. However, I have some small objects that I switched to inches for easier creation (or so I thought). Now near the completion of the scene, I cannot maneuver around in the perspective viewport without the screen going gray on me. It like scrolls out to where I just see the compass and lighting system. So from what I’ve found on various sites as well as here, it seems that my units are conflicting with one another. The problem is, I don’t know how to change them….My teacher really has been totally worthless. I should have just studied on my own because this is what I’m doing anyway.

    Comment by Melljoy — December 11, 2012 @ 19:33

  12. Hey, Melljoy, the easies way, probalby, will be for you to just go to the scenes with Inches and in the Units Setup, just switch back to Meters (make sure to reset x-forms, just to make sure) and re-save. This will re-scale your scene. Then re-merge these objects into your master scene. But, bear in mind, if you have any rigging systems in place, it might screw your scene completely up. Fixing units mis-matches is not easy and is highly individual depending on your shots. But, my suggestion should work 99% of the times for static scenes.

    Comment by loocas — December 31, 2012 @ 13:10

  13. hei,
    hell, my 3dsmax model is in Inches, amd I want to convert it to meters, But the value in Inches is the value I want to reach in meters… For exemple in my case, the Display unit scale is in meter and I have an object which measure 12m but the system unit setup is in Inches… And when I change it to meters my object is sudenly 472m long instead of 12m as I would like it to be…
    What the fuck should I do to correct that? I didnt find the place to change the scale….
    It is hell fucking irritating…

    Comment by fred b — January 21, 2013 @ 12:37

  14. It is irritating. :) You should have set your units beforehand, now you’ll have to deal with scaling back your models, which isn’t that big of a deal, if you haven’t done anything else than modeling (such as rigging, hierarchies, UVs etc…). Good luck, mate.

    Comment by loocas — February 21, 2013 @ 12:10

  15. A clear, helpful explanation available here:

    Comment by Tank — March 13, 2013 @ 15:44

  16. Excuse my english.
    I’m a realy newbie in 3DS Max, but i use from about 15 years CAD programs. So i did this: I create a box in CAD, 1mx2mx3m, and exported it in dwg format. I opened 3DS, imported the dwg file, customize – units setup and play with Display Unit (DU) and System Unit (SU).

    – DU=mm – SU=mm – box=1mmx2mmx3mm (mm/mm=1)
    – SU=cm – box=10mmx20mmx30mm (cm/mm=10)
    – SU=m – box=1000mmx2000mmx3000mm (real dimensions)
    – DU=cm – SU=mm – box=0.1cmx0.2cmx0.3cm (mm/cm=0.1)
    – SU=cm -box=1cmx2cmx3cm (cm/cm=1)
    -SU=m – box=100cmx200cmx300cm (real dimensions)
    – DU=m – SU=mm – box=0.001mx0.002mx0.003m (mm/m=0.001)
    – SU=cm – box=0.01mx0.02mx0.03m (cm/m=0.01)
    – SU=m – box=1mx2mx3m (real dimensions)
    So, SU is important to be the same with reality, with this unit 3DS is working. DU is the unit that you input from the keyboard to create the object to its real dimensions.
    I hope I understood correctly, and i explain it right.

    Comment by a newbie — April 9, 2013 @ 11:16

  17. just reading your : “for the slower ones…” made me go away from your arrogant post.

    Comment by Sergio — May 22, 2013 @ 22:41

  18. Arrogant? Heh, yeah, I’ll remind you of what it means when you fucking hand me over a file in Inches with rigging and animation to be merged in the rest of the shots made in centimeters. I’ll love you for it. In fact, I’ll fucking smack you across the face and point you to this exact “ARROGANT” post.

    Comment by loocas — May 23, 2013 @ 17:25

  19. Calm your farm…

    Comment by Wys — June 26, 2013 @ 06:32

  20. Hi

    I work with large scenes, huge landscapes.
    My issue with max is when I export from Rhino, which is setup in MM. I then take it to max which I assume to setup in MM both in display and system setup. But the problem of zooming out from the imported model becomes a problem the scroll zoom function just stops, and instead I have to pan around the model in every view port apart from the perspective, which has no problem at zooming in and out. – question is; is that normal or I have set up max wrong?

    In order to correct this zooming and display issue, I keep the display units as MM and change the system units to meters. and then import model again from rhino and tick the scale button.

    But this seems to make model really small, but at least usable.

    Basically why on earth does max have zooming issues and display issues with large models??

    Comment by hazzler — June 27, 2013 @ 12:48

  21. you r total ass

    Comment by mourad — July 11, 2013 @ 06:48

  22. “you r total ass” writes an anonymous guy. Priceless :)

    Comment by loocas — July 13, 2013 @ 12:56

  23. I understand how you must feel and I’m sure you’re a very knowledgeable and reasonable person in your other posts as said in your edit, that said I only found this blog from looking up how to change the units for 3ds Max and I’m sure I’m not the only one.

    So after filtering out the useless and yes, bloody annoying but obviously well needed on your end ranting, thank you for your info, was helpful. But as a reader, just as a future reference, I wouldn’t return, nor bother to read any other posts because of the impression I got of you from this one.

    Comment by sage — August 5, 2013 @ 11:16

  24. Too bad, sage. If you weren’t such a pretentious pussy, you might have learned something useful you didn’t know before. ;)

    Comment by loocas — August 8, 2013 @ 00:54

  25. Yes its your blog and you have the right to be smug and/or rant and rave about whatever you want, but why even bother pretending to be helpful. All that is learned here is that your an arrogant bitch who would probably shout at the old lady for not pulling the chain to stop the bus even though it was “right in front of her fucking eyes”. incidentally, if I graduate from MIT do they give me an MIT. I realize you state I don’t have to “have a MIT in …” anything but I was curious if this MIT thing is better than my degree. Circumstances will sometimes have people doing things beyond your understanding and clearly your not bright enough or lack common social skills to realize this. So have your little tantrum but don’t expect any civil discourse from the rational grownup world. Now come at me however you wish or don’t… I don’t really care and won’t be back to this sad little blog to learn.

    Comment by Me — August 17, 2013 @ 20:20

  26. Sure, sure, “ME”, don’t come back, or, whatever. I kinda don’t give a shit, to be honest. If all you took from the article is the rant, well, your bad…

    Comment by loocas — August 31, 2013 @ 18:49

  27. Dude, so mean. hahaha but your rant explained it perfectly. Hahaha funny instructive post THank you

    Comment by Milkoz — October 28, 2013 @ 16:38

  28. Excellent post! I have been working in the games industry for many years and I am one of the ‘artists’ that feel uncomfortable with anything remotely technical. I tried to rig a character the other day, which is something I’ve stayed away from for a long time. I got a little confused and frustrated when my display meter values weren’t matching the numbers shown in my slider joint limits. Your blog helped me to work out that I was indeed being retarded, after spending the past ten minutes ranting about how utterly shit Max is. Oh the irony.. :D

    Comment by John — November 9, 2013 @ 18:05

  29. Glad to have helped, guys. :) That was the sole purpose of this rant, which seems to have worked! :)

    Comment by loocas — November 14, 2013 @ 18:22

  30. Thanks for the info, great post!


    Comment by wserlopz — January 10, 2014 @ 05:49

  31. Thanks for The explanation. Units are rather straightforward, but I’m glad someone finally outlined exactly how it works in Max. I’m pretty sure the ‘Anger/Ego’ mentioned by a poster is really just a stylistic choice. I get it, I found it kind of funny. My only advice is the same I give pretty much any tutorial– try to cut out the fat, draw a line between education and entertainment.

    Comment by jg — January 15, 2014 @ 02:49

  32. Thank you for your tip. Fixed an annoying thing with default wrong texture sizes too (1×1 inch instead of 1×1 meters).

    Comment by Happy Dayz — January 25, 2014 @ 16:34

  33. @loocas You must of been teased a lot as a kid… poor thing.

    Comment by Brian — June 4, 2014 @ 13:29

  34. thnx sir i got a problem i set my unit but the unit is not corect my autocad file window size is 4 or 5 or 6 feet but in max when i draw a box they show me the size 20′ 40 ‘ etc how i reesolve thiz problem thnx sir

    Comment by asif — June 30, 2014 @ 11:45

  35. hi we create content with 3ds max set to meters. e.g. 3000 models, all correct size in meters.
    so far so good. but now folks in usa buy it, and they have 3ds max set to feet.
    and when those folks who have 3ds max set to feet, open our content, it is
    the wrong size. e.g. a 1 meter cube is not 33 inches. instead it is about 10inches and needs a 3.3x multiplier. for every one of the 3000 models. which makes folks in the usa, who buy our junk very angry.
    we cannot ask the user to change display measurement to meters, as they probalbly have a house and whatever in feet, and just want to add our trees in the correct size in feet.

    i am happy to give you a ton of free models for the correct answer to what we can tell our customers to do who use 3ds max in feet.

    Comment by stewart — July 25, 2014 @ 00:42

  36. there is no rigging by the way. and i dont want to open, change units, resave, 3000 models for US market right….? to simplify. we built our models in europe, in meters. we want to hjave them work in both meters and feet customers of fucking 3ds max.

    Comment by stewart — July 25, 2014 @ 00:48

  37. Actually, no.

    Comment by loocas — July 25, 2014 @ 23:01

  38. Seriously, edit the swearing and yelling out of your article. Every time I look at these dialogs in Max I’m going to remember that out-of-control angry, pathetic blogger who shat mountains over people not understanding them. Your attitude is ten times worse than any alleged stupidity you could be upset about.

    Comment by Alex — August 5, 2014 @ 21:05

  39. Holy cow–I hadn’t read the comments! Even sadder than your cursing rage is the way you defend and justify it when half a dozen visitors complain about it (while fewer and even sadder visitors enable it). You haven’t offered any reasons to your visitors to hope that you’re the kind of fella who alters his behavior, provided feedback. (And yet they go on hoping, and telling you so–while you ignore their input.) I’m ashamed to have dignified your barbaric dialogue by engaging in any commentary at all.

    Comment by Alex — August 5, 2014 @ 21:42

  40. Alex, with all due respect, fuck off if you don’t like my blog. Cheers…

    Comment by loocas — August 10, 2014 @ 12:43

  41. Yeah well it’s not fucking intuitive is it? Maybe that’s the fucking problem fucking artists have with the thing. The relationship between 3ds Max’s fucking “units” and real world “units” isn’t defined or readily apparent. When you’re used to just working in fucking Max for ages making shit for digital endpoints the task of then setting it up to create something using real-world is really fucking daunting and a fucking exercise in frustration the first few times. Fucking Autodesk doesn’t give a fuck about improving their fucking software so the units setup remains as fucking archaic as it has for close to two fucking decades. Demeaning people because of some fucking bloated fucking software companies shortcomings is fucking rude.

    Comment by Angus McDangle — October 17, 2015 @ 01:23

  42. GOOD, GOOD

    Comment by loocas — November 13, 2015 @ 21:36

  43. Thanks for this thread, yup I’m reading this in Dec 2015. This is right. and some hypothesis are also correct. I think 3ds Max 2016 fixed this in SU options including material units.

    Comment by bocs — December 7, 2015 @ 08:58

  44. Very basic stuff. So you’re ranting at completely new people who may not understand file variance. You do have to dig in the manual a bit to find even this basic information you’ve outlined. I googled “3ds Max unit setup resulting accuracy CPU impact” and got this beginner’s tutorial rant. I get the feeling by your comments that you were previously employed but are no longer… with good reason. This attitude doesn’t belong in a workplace. I get gfx devs that make this mistake. I politely teach them knowing the nature of Max. Either you’re going for a Lewis Black stab at comedy or can’t handle management. Why even write a help article if you can’t handle helping? Looking for work so you wrote a tutorial? A change of attitude will do you wonders. At any rate… I’m going to continue searching for my answer. Have a good day!

    Comment by Drew — December 16, 2015 @ 19:31

  45. Yes, very basic, thus I never understood why people always kept fucking it up, hence this tutorial. As for my employment, well, since I’m my own boss these days, I’d say I’m all right. But thanks for caring, man. :) Hope you find what you’re looking for.

    Comment by loocas — February 4, 2016 @ 20:58

  46. Hahaha, I love the rant. I’ve experienced lots of problems with people using the wrong system units also. It does get tricky when working in Europe with people in the USA and get additional scenes which can be set up differently also from different studios.

    My advice to Stuart, the guy with the 3000+ models is to make sure all meshes are collapsed to editable polys with UVs baked in and make sure none of the bitmap inputs have ‘use real world scale’ ticked on. Then tell his customers to x-ref in the object and select for Max to automatically scale the object to the scenes system scale, then from there merge the object into the scene through the x-ref dialog box.

    Comment by Nick — April 20, 2016 @ 11:56

  47. I feel you mate. I feel you. I’d just read this entirely out loud (like i think should be read) to my artists that keep sending me file completely out of scale. And here they comes, the man became Tormund the giant and the plane a f****** toy!
    Keep doing this o/

    Comment by Daph — June 30, 2016 @ 17:54

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