Is it possible to open multiple files?

I have a long list of individual files I would like to open them together


No, but you can open multiple concurrent instances of Rhino as your system resources permit and each one can have a different file open. You can copy and paste between them.

Hi Dewitt - do you want all files to come into one file? You’ll need to open the first one and Import the others- this can be scripted or even macroed with a text file (ReadCommandFile - see Help)


Or just open a blank file with the units you want, then in Windows explorer select all the files and drag them into the Rhino window, and choose “Import” in the dialog.

Otherwise, there are also a few “batch import” files floating around…


Windows 8 TIP: This drove me crazy until I figured it out. If you go to the start screen and click on Rhino, it will just make the current Rhino active and NOT open up a new instance.

So … SHIFT-CLICK on the Rhino icon and you’ll get a new instance.


I really don’t get this “one file only” limitation for rhino.
What is it good for?
Why can’t we open multiple files (and possibly arrange neatlyin tabs) like just about any other windows program around?
Maybe this should be added to the wishlist for V6?

Is this a good idea? Depends…

If you have an MDI (multiple document interface) and have one of the “tabs” crash, IF it takes down all the others with it, it is definitely NOT a good idea…


The Rhino UI already has two sets of tabs, one for command icons, one for viewports. Since Windows XP multiple instances of the same program are grouped in the taskbar. I really don’t see why Rhino would need to implement another row of tabs.

For Rhino 4 that “one file but multiple instances” made perfect sense on 64bit systems. Each instance of Rhino could use all of the 32bit memory limit up to the physical memory limitation. That’s obviously not an issue for 64bit Rhino5 anymore… but then there’s what Mitch said. I had some crashes with multiple files open and was happy to see only one file go down.

So… in what case would MDI superior to the current concept?

Hi Norbert,

Another advantage is that you can assign cpu priorities to different instances.
Making it workable to have one instance do an operation in the backgound with low priority while your active instance is at normal priority.



Multiple files can be open together in Rhino using the Worksession command. Only one is “active” at a time, the others are attached. The geometry in all files can be seen together (unlike opening multiple instances of Rhino). You can copy geometry from the attached files, and use it as references to build geometry with, etc. But you can not change the contents of the attached files, only the contents of the active files.

The active file can be easily changed in the window which is opened by the Worksession command. Open the file which you want to have as the first active file. Then use the Worksession command to attach other files. A window opens Other files can be opened with the Attach button.

To change the active file type Worksession and a window opens. If the file you want to be active is already attached select it and click on the Active button. If the file is not attached then you need to attach it first before making it the active file.

Worksession setups can be saved. Worksession files are small because they just contain the names of the files in the worksession, not the files’ contents. This makes going back to a particular set of active and attached files simple and quick.

Worksession may have been originally intended for multiple users sharing files, but it is a great tool for single users with complex geometry, or geometry which results in large files such as meshes from scans.

1 Like

There certainly are some arguments why not having open multiple files in one instance of rhino is a good idea in some cases.
But to be honest, these arguments would be valid for almost any other (cad and non-cad) program, and I don’t see to many users complaining about the “problem” of allowing for multiple files.
The various files could also be sandboxed like google chrome sanboxes different tabs, so a crashing file wouldn’t crash rhino.
And finally allowing multiple files does not neccessarily mean disallowing multiple instances giving the user the possibility to “isolate” problematic or heavy files in a different instance of rhino.

I admit this might lead to some confusion and might be difficult to grasp by the user though.
I also got used to opening multiple instances of rhino, but I suspect this is using more recources (just guessing, no expert)?
Anyway, I just found it an odd behaviour, so no high priority wish for v6.

Cheers, Norbert

Resources is a good point. Wouldn’t sandboxing each file prevent you from sharing resources?

Thanks everyone, by way of explanation we have a bunch of files that are components of a larger structure, that we are preparing for fabrication, I need to scale all of them and wanted to just open them in one file for that operation.

the discussion has been helpful, thank again

This is an AutoCAD style holdover and violates basic UI principles in both Windows and OS X. Chrome runs each window as a separate instance, but still unified under a single application UI. I really hope this is addressed in V6!

Can’t see how having each file in a separate instance is violatin anything Windows UI related. Ever opened multiple files in Office?

OSX and Chrome UI aren’t exactly relavent references for Windows UI…

Geomagic has all files open in a sort of MDI and I’ve had it lock up and crash all the open documents so I’d like Rhino to stay the way it is.


1 Like

It’s frustrating to have to navigate to a file in Windows to open the file instead of being able to File > Open from within Rhino. I feel like I’m using ACAD R14 every time I have to open a file.

You can set:
_Run Rhino.exe
to an alias and open your file from the new instance. Not perfect, but it’s what I use.

1 Like

Rhight-click the Rhino shortcut, open Rhino, then open dialogue is the fastest for me.

Cheers, Norbert

Drag and drop works

1 Like