CAD tip # 7103:

Question CAD
% platform category

How to convert a drawing from inches to centimeters (or vice versa)?

First of all - an AutoCAD drawing in the modelspace is unitless. A drawing unit can be anything you wish. A square of 10x10 units can be 10mm, 10m, 10", 10 feets, whatever. The real physical units are required only when you want to represent the drawing model for the real world - for dimensioning, plotting (plot scale), paperspace and annotation functions.

But if you really want to scale your drawing from inches to milimeters, centimeters, meters - or vice versa - e.g. from centimeters to inches (i.e. between metric and imperial units), you can use the SCALE command.

When going e.g. from inches to centimers, you have to scale up your drawing 2.54x. Run the SCALE command, select All objects, specify *0,0 (global) as the reference point and enter 2.54 as the scale factor.

You can prepare a menu macro button to perform this conversion operation automatically (menu macros use ";" instead of Enter) - some examples:

[Inches->CM]^C^C_SCALE;_All;;*0,0;2.54;
[Inches->MM]^C^C_SCALE;_All;;*0,0;25.4;
[CM->Inches]^C^C_SCALE;_All;;*0,0;0.393701;

In newer AutoCAD versions (2006 and up) you can simply set the correct units in FORMAT>UNITS>INSERTION SCALE in both drawings - when you then insert the xref/block, AutoCAD will scale it for you automatically - it is far less painless. (thanks kris.treagus)

To perform a formal change of units without changing geometry, use the command UNITS.

To automatically convert the scale/units of existing objects and blocks to insert, use the command -DWGUNITS:

ACADLT

* CAD

10.12.2009 69009× FAQ

Comments Tell a friend

Prices - CAD eShop:

AutoCAD

AutoCAD LT

applies to: AutoCAD · AutoCAD LT ·

Back All CAD Tips

Switch AutoCAD to TURBO mode. « | » Render error: The following render appearance images are missing

Have we helped you? If you want to support the CAD Forum web service, consider buying one of our CAD applications, or our custom software development offerings, or donating via PayPal (see above). You may also add a link to your web - like this "fan" link:

CAD: OS: Categ:
Text:	FAQ glossary

Featuring:
Increase your productivity with our set of add-on functions for AutoCAD Civil 3D
CADstudio Civil Tools More info

Please use these tips at your own risk.
Arkance Systems is not responsible for possible problems that may occur as a result of using any of these tips.

CZ \| EN \| DE
Login or
registration
	Visitors: 4285

	CAD Forum - tips, tricks, utilities, help, how-tos and FAQ for AutoCAD, LT, Inventor, Revit, Map, Civil 3D, Fusion 360, 3ds max and other Autodesk software (support by Arkance Systems)	Arkance Systems CZ s.r.o. (CAD Studio) - Autodesk Platinum Partner & Training Center & Consulting Services Partner	CONTACT: webmaster.cz@arkance-systems.com tel. +420 910 970 111
	Copyright © 2023 \| Advertise with us \| Online privacy