How do I resize an object to specific units?

Hello all,

How do I resize an object to specific blender units (or feet / inches, if possible)?

When I resize an object, in the lower left-hand side of the 3d frame, it shows the X, Y, & Z sizes. These are percentages of the original, right?

I’ve read a few tutorials on blender and I’ve used (a little bit) programs like Caligari TrueSpace. But that’s all I know about it so please don’t answer with really complicated terms. :wink:


I’ve asked this question too; unfortunately nobody replied to the previous post. When I’m modelling things in different scenes and linking/appending them later, it’s very important to have everything sized to a certain fixed scale.

I haven’t been able to find any ‘absolute resize’ or ‘size to length’ feature in Blender yet.

I found this tutorial which says:

Finally the key n allows you to change your object by entering its coordinates on the keyboard (more precise).

I think that’s what I needed to know.


This doesn’t actually do the trick. The manual entry that N brings up lets you position objects absolutely, but not size them. Sizing is relative to the object’s original size (1.0). I’m looking for a way to instead use absolute values for the size, based on the maximum absolute X/Y/Z size of the object.

N brings up lets you position objects absolutely, but not size them.

I think you’re misunderstanding something fundamental here. Any Object (not dupliverts but real objects) has an absolute (global) size, in BU (blender units) when added. If you change that size in the N tab you change the absolute size. Admittedly it’s cludgy in that you have to do it on all three axii to get that final, absolute value you’re looking for, but, with the ammount and volume of requests (and sometimes demands) for CAD-like, numeric input functions, I can understand why it’s done this way.

S, 2 will scale an object from absolute 1 to absolute 2, and S, 2 again will size it to 4.


What I mean to say is that object size (the Size X, Y and Z on the transform properties panel) is a scaling factor rather than an actual size.

If I create a square plane, it defaults at 1x1 BUs. If I enter editmode, and move the vertices to make it a 2x1 BU plane, Size X, Y and Z in the transform properties panel will still all be 1.0.

I definitely agree that Blender should remain an artistic-oriented application, rather than CAD, but I don’t think what I’m looking for is related much to CAD. What I’d like to do is quite important for large art and animation projects, where many different props/sets/characters are stored in different scenes.

What I’d like to do is have a set of input boxes with BSizeX, Y and Z. Where BSize is the size in that dimension of the object’s Bounding Box. So when I move those vertices to make the 1x1 plane into a 2x1 plane, that change is visible somewhere, and I can scale based on that.

If I enter editmode, and move the vertices to make it…

In that case you are not editing the Object but (in this case) the Mesh. The Mesh is a seperate DataBlock linked to the Object.

But I hear what you’re saying; that when the size of the Bounding Box should be reflected in the Global size of the Object. (I’m wondering how this will affect Import and Export though).


Yeah, given the datablock divisions I figured that was the deal; internally I imagine it’s glSize being applied to the mesh data as a whole.

The work-around I have now is to create that default 1x1 BU plane on a separate layer and use it as a ruler. If I then want to make an object, say, 20 BU tall I can scale the plane, then manually scale/transform my object until its top and bottom hit the edges of the plane on-screen.

Maybe this is more the subject for something in the Feature Requests Tracker.