How to reduce the size of your Auto CAD file?

there are many ways to reduce the size of CAD files

1. use command purge to get rid of bad/unused layers.
2. use command audit or recover to fix any errors in the file.
3. it's perfered to use all of the above together. 

Try

1. Type AU (Audit)

   - Type Y (Yes)

2. Type PU (Purge)

   - Click "Purge All"

   - Click "Purge All" again

   - Click "Close"

purge your drawings. your file still contains the blocks and dimensions you deleted. then audit. And if you really want to make it smaller, explode your blocks. I don't recommend it but if you plan to shrink your file do it. now if your drawing doesn't contain any blocks, convert your drawing into a single block. this will greatly reduce the size of your file.

overkill.

it will delete the extra lines and will reduce the drawing size

I won't add more to what have been said already.

I normally hit p enter then a enter to purge all.. easy and fast

Best Options :-

1. PURGE

2. OVERKILL

3. DELETE UNNECESSARY LAYERS

4. AUDIT

5. IF YOUR FILE SIZE STILL NOT REDUCE PLEASE COPY WITH      BASEPOINT WHAT U NEED ACTUAL THEN PASTE IN NEW            FILE.

AFTER COMPLETE THE ABOVE OPTION CONVERT/SAVE IN ZIPPED FOLDER.....

THANKS,

MUSTAFA

Audit doesn’t reduce file size. But it is recommended to do file audit before we continue with other process. It will maintain the drawing integrity and fix errors that might prevent us to remove unnecessary objects.If you are not familiar with audit, you can run it by typing AUDIT at command prompt then press enter. After you audit the drawing you can run PURGE. You can type PURGE at command line then press enter. AutoCAD will open a dialog box like below.As you can see in the list, you can purge or remove unused objects. Block definitions, styles, materials and layers.  Regapps stands for registered applications. To purge regapps you need to type –PURGE (with the – prefix) then enter. Type R for regapps then enter again. In many cases, purge regapps can significantly reduce the file size.  Purge removes unused objects. WBLOCK works differently. With WBLOCK you choose objects that you need and save it to a new clean file. So you left the excess in the origin file. You can activate WBLOCK by typing WBLOCK then press enter. Using this command is very similar to creating block. This command was originally for create block as external DWG, but we can use it for this purpose as well. 

here's the link where you will find the answer related to your query: 

20 Ideas for Speeding Up AutoCAD

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