PDF is one of the world’s most useful and versatile file formats. Unlike many of its competitors, it doesn’t require any specific software; users can open it using any standard web browser. Add in its ability to contain a variety of different graphical information in addition to text, and you have the recipe for a wildly popular format.
Nonetheless, PDF files aren’t perfect. Their strength in wide compatibility often proves a weakness in other areas. In short, they’re great when you only need to view a document; less good when you need to edit it. This can prove a particular problem if you work with software such as AutoCAD.
Luckily, there are ways to convert even the most complex PDF to AutoCAD-compatible file formats. In this guide, we’ll run through the reasons why you might need to perform such a conversion, provide a rundown on what not to do, and show you the best ways to convert any PDF to AutoCAD.
Since its initial release in 1993, PDF has become a ubiquitous file format across the globe. Its popularity lies in its ability to display documents in an identical manner on virtually any device. This gives it an edge over formats such as Microsoft Word’s .doc and .docx formats, which can have inconsistent appearances on different displays. Meanwhile, its ability to store text gives it a clear advantage over simple raster file types.
The ability of PDF files to display various forms of data makes them harder to categorize than many other formats. PDFs are able, for example, to display raster images, such as photos or scanned sketches. However, they can also contain vector graphics—though they typically only support simpler entities, such as circles and lines. As a result, PDF is neither strictly a vector nor a raster file type, but a sui generis format.
There are obvious benefits to the complexity of PDF files—but also some drawbacks. A key issue is that PDF files exist to display information. If you wish to edit the contents of a PDF file, you’ll need to convert the file to another format in order to edit it in another program. A common editing software in the CAD industry, for example, would be AutoCAD. However, this conversion process can throw up numerous issues. This means that specific steps must be taken when converting from PDF to AutoCAD-compatible formats.
As mentioned above, AutoCAD is one of the most commonly used CAD programs on the market. It is the flagship software from Autodesk, and offers users powerful 2D and 3D CAD functionality. For this reason, it is popular across a variety of industries, though it is particularly prominent in the AEC sector. Thanks to its linked application, AutoCAD 360, its users can now work on mobile devices or edit from the cloud.
AutoCAD allows its users to create detailed and accurate technical drawings: a must-have for engineers, architects and product designers. It also allows the attachment of relevant data to these drawings, transforming them from simple images into vital tools for the successful completion of a project.
The complex information that AutoCAD deals with requires a file format capable of storing it. Raster file types, which simply store color information, are, therefore, unsuitable. Instead, vector file formats are necessary. These formats store each object (such as a line or circle) as a separate, editable entity, to which a user can attach additional data. AutoCAD supports many different file extensions, though two stand out in particular: DWG and DXF.
The history of the DWG format goes hand in hand with that of AutoCAD itself. DWG has acted as the native file format for AutoCAD ever since its first release in 1982, and stands as one of the most popular file formats in CAD. Due to its popularity, there are also now a number of ways to view DWG files without AutoCAD.
Given its status as AutoCAD’s native file format, it should come as no surprise to learn that DWG is a vector file format. In fact, Autodesk updates the DWG format periodically to reflect changes to AutoCAD itself. This means that DWG is the ideal format for loyal AutoCAD users—particularly those who make use of AutoCAD-specific entities in their drawings. Additionally, DWG also supports both 2D and 3D graphics, making it a flexible choice for designers.
Though DWG is AutoCAD’s native format, Autodesk is well aware that it isn’t always a designer’s ideal choice. That’s why it created the DXF file format. Unlike DWG, which is intended primarily for use in AutoCAD, DXF is an open standard. This means that virtually any CAD software on the market can open a DXF file. As such, it’s ideal for users who often collaborate with designers who use alternatives to AutoCAD.
DXF is, in many ways, similar to DWG. Both are vector file formats, capable of displaying objects and data present in AutoCAD drawings. However, there are some key differences. DWG is intended to reflect the full range of AutoCAD entities and features. DXF, meanwhile, is meant to act as a lingua franca for many different types of CAD software. As such, it does not support many of the AutoCAD-specific entities that DWG does. It also lacks support for 3D graphics—though, unlike DWG, it is a suitable format for CNC machines.
Converting from PDF to AutoCAD-compatible formats
The PDF format, with its purpose as a medium for displaying information, differs completely from formats such as DWG and DXF, which are for creating and editing designs. However, oftentimes, designers will find themselves needing to edit designs stored as PDF files in AutoCAD.
The solution, therefore, is to convert their PDF to AutoCAD-compatible formats. Unfortunately, this is often easier said than done. Given the combination of raster data, vector entities and text that can make up a PDF, conversion can be tricky. That’s why we’ve put together this guide showing you the best way to convert your PDF to AutoCAD—with information covering raster, vector, and mixed files.
How not to convert from PDF to AutoCAD
Before we jump into the ways to convert from PDF to AutoCAD, let’s start off with a quick note on how not to do it.
For starters, it’s worth noting that, as useful as Google can be, it can often throw up some less-than-perfect results when it comes to PDF to AutoCAD conversion. Many of the first results you’re likely to find in a standard Google search will be online converters. These tools are generally free—but, as the old adage goes, you get what you pay for.
The quality of any conversion produced using an online tool is likely to be low—too low, in fact, to be useful in AutoCAD. Worse still, online conversion tools can leave you open to intellectual property and security risks. If you’re still tempted, make sure to check out our guide covering the pitfalls of online converters.
Meanwhile, some users may wish to try out manual tracing before committing to an automatic conversion tool. A key issue with this is that, whilst many manual tracing tools readily accept various raster file types, they often don’t support PDFs. If, somehow, you do find a tool that allows for manual tracing of PDFs, you’ll come up against another issue: manual tracing is hard. The process is time-consuming and demanding.
It’s certainly true that, if you have the time on your hands, you can achieve good results. However, PDFs can often contain a wealth of complex information. This means that achieving a great quality vector image through manual tracing usually isn’t worth the trouble. Visit our comparison of manual and automatic tracing for more information.
Importing PDFs directly into AutoCAD
For many years, it was impossible to directly import PDF data into AutoCAD. This all changed with AutoCAD 2017: the first release to include PDF file imports as a feature. Earlier this year, Autodesk built further upon this capability when they released AutoCAD 2018—the most recent version of the software.
Now, it’s possible to import some PDF data into AutoCAD using the PDFIMPORT command. Supported data types include some vector geometry and text, including SHX text as of AutoCAD 2018. If you use this command, AutoCAD will import the data directly from the PDF, enabling you to edit this data and later save it as a DWG or DXF file.
However, it’s worth noting that this command has its limitations. To begin with, the PDFIMPORT command does exactly what it says on the tin—it imports data from a PDF. Whilst this might sound ideal, it can often cause problems. That’s because PDFs only support simple vector entities; AutoCAD, meanwhile, supports much more complex entities, and these might be necessary for your project. If you’re simply importing rather than converting, you could be missing out.
Still, AutoCAD does allow you to transform your vector PDF data into editable geometry. This is not, unfortunately, the case for the raster data in your PDF. The PDFIMPORT command will simply attach any raster data to your AutoCAD drawing as an xref, instead of converting it. If you have drawing data saved in the form of a sketch, this is, therefore, unsuitable for your needs.
Scan2CAD is the ultimate vectorization software, enabling users to convert to and from a number of different raster and vector formats. This includes the ability to vectorize PDF files in just a few clicks.
Scan2CAD’s automatic PDF-to-vector conversion makes it an ideal choice for any AutoCAD users looking to edit their PDFs. That’s because, unlike some other tools, it’s capable of converting both raster and vector PDFs. It can even handle PDF files which contain both raster and vector elements. Read on to learn exactly how to convert each type of PDF to AutoCAD.
Converting a raster PDF to AutoCAD
From a software point of view, raster-to-vector conversion is incredibly complex. That’s because raster images and vector graphics are totally different. A raster image is made up of colored pixels, whilst a vector image is made up of mathematically defined objects.
The only way to get from raster to vector is through automatic tracing. This involves Scan2CAD working out the appropriate vector entity types for different parts of a raster image. It’s trickier than it sounds!
Luckily, for a Scan2CAD user, the conversion process is simple. To begin with, try to ensure you use a good quality PDF—if necessary (or possible), rescan images to improve their quality. Once you’re happy that your raster PDF is good enough for conversion, load it into Scan2CAD.
Before starting the conversion process, select the best vectorization settings for your image. After that, there are three ways to vectorize your image:
- : which converts lines, curves and shapes to vectors.
- : to convert raster text to vector text.
- : which converts the entire image (both lines and text) to vectors.
Finally, all you have to do is save your image as an AutoCAD-compatible format: DXF or DWG. And that’s it!
Converting a vector PDF to AutoCAD
If your PDF file consists entirely of vector graphics, you may assume that the conversion process is simpler than that of a raster PDF. In some ways, this is true: Scan2CAD won’t need to perform the complex automatic tracing operations involved in vectorizing a raster image, for example.
However, converting from PDF to AutoCAD-compatible formats such as DWG and DXF throws up its own set of issues. This is because PDFs support only a limited range of vector entities. Additionally, some information is lost when saving a drawing in PDF format, resulting in elements being saved incorrectly. When converting your PDF to DWG or DXF, you’ll therefore have to convert these to the correct entities.
Luckily, Scan2CAD makes the process easy. Simply start by loading your vector PDF in Scan2CAD. Use the View Vector Colors tool to turn off the “true” colors of your vector PDF, and instead color vectors by type. You’ll then be able to explore your image, and see whether your entities have been imported correctly. If not, you can change Scan2CAD’s PDF Import Settings to suit the needs of your image. Settings include:
- Make Arcs, Beziers, Circles, Dash Lines, and Arrow Lines
- Load PDF Text
- Load Solid White Rectangles
Once you’ve chosen appropriate settings, you can re-import your vector PDF. The vector elements in your PDF should now appear correctly. If you’re still experiencing any issues, check out our guide to common DWG conversion problems to iron them out. Once everything is sorted, you can save your image as a DWG or DXF.
Converting a PDF with both raster and vector elements
Last, we’ll come to the most complex conversion of them all: converting a PDF containing both raster and vector graphics. Scan2CAD, however, makes this conversion a cinch.
Simply start by loading your PDF into Scan2CAD. You’ll see a dialog window pop up immediately if your file contains both raster and vector elements, with check boxes prompting you to load the raster elements in the PDF, the vector elements, or both. Ensure to check both boxes to convert all elements from PDF to AutoCAD.
From this point, the conversion process basically involves a combination of the two above elements. Using the View Vector Image and View Vector Colors tools, you can isolate the vector elements of the PDF, allowing you to judge the PDF Import Settings you need to use. You can then re-import your PDF, and all vector elements in your file should appear correctly.
Then, use the View Raster Image tool to show only the raster elements of your PDF. Follow the steps in the raster PDF to AutoCAD section above to vectorize these raster elements. Now, all elements in your PDF file should have been successfully converted to vector. All that’s left to do is save your image as a DXF or DWG file—and you’re done!
We hope this guide has covered everything you need to know on converting from PDF to AutoCAD. If you’re still curious, though, feel free to leave any more questions in the comments!