Explainer · what is a pc3 file

What is a PC3 plotter file, and why use one?

DWGDXFFree1,042 words

By Sumana Kumar · Published 30 Nov 2023 · Updated 3 Feb 2026

A PC3 file is a saved plotter configuration in AutoCAD. Rather than choosing a printer and re-entering its settings every time you plot, you store those choices once in a PC3 — the output device, the available paper sizes, custom paper definitions, and device-specific options — and then pick that configuration whenever you print. It is how AutoCAD turns 'set up the plotter' from a repeated chore into a one-click selection.

The PC3 covers both real printers and AutoCAD's built-in software 'plotters'. The most familiar example is the DWG-to-PDF configuration: that PDF output you get from AutoCAD is produced by a PC3 file acting as a virtual plotter. So even if you never touch a large-format printer, you almost certainly use a PC3 every time you publish a drawing to PDF.

Understanding what a PC3 stores, and how it teams up with plot styles, demystifies AutoCAD's printing and explains why plots come out the way they do.

What a PC3 stores

A PC3 captures everything about how AutoCAD talks to a particular output device. That includes which device or driver it points at, the list of paper sizes that device offers, any custom paper sizes you have defined, default print quality or resolution, and device-specific options like duplexing or media source. Bundling all of that into one named file means selecting the PC3 sets up the whole output environment at once.

Crucially, a PC3 is about the device and the paper, not about how your lines look. The distinction between 'where and on what I print' (the PC3) and 'how thick and what colour my lines print' (the plot style) is the key to AutoCAD's plotting model, and keeping the two ideas separate makes both easier to manage.

Real plotters and virtual plotters

PC3 files come in two flavours. Some represent physical hardware — a specific large-format plotter or office printer — with that device's drivers and capabilities baked in. Others are virtual: software plotters that produce a file instead of paper. The DWG-to-PDF plotter is the everyday example, and there are similar configurations for raster image output and other formats.

This is why 'plotting' in AutoCAD does not always mean putting ink on paper. When you publish a sheet to PDF, you are plotting to a virtual PC3 that writes a PDF file. Recognising that the PDF output and the office plotter are both just PC3 configurations makes the Plot dialog far less confusing — they all appear in the same device list and behave the same way.

Creating and editing a PC3

You manage these files through the Plotter Manager, reached from the Plot or Page Setup dialogs or by typing PLOTTERMANAGER. Inside it, the 'Add-A-Plotter' wizard walks you through creating a new configuration: choose the device or driver, give it a name, and AutoCAD writes a new PC3. To change one later, open it from the Plotter Manager and edit settings like paper sizes, custom sheet definitions and device properties.

A common reason to edit a PC3 is to add a custom paper size the standard list does not include, or to tweak margins so a drawing fits a particular sheet. Once saved, the configuration is reusable across drawings and shareable with colleagues, so an office can standardise on a known-good plotter setup rather than everyone configuring printers independently.

PC3 and plot styles work together

A PC3 decides the device and paper; a plot style table decides how objects appear on the page — line colours, lineweights and whether colours map to black or to specific pens. These are the colour-dependent (CTB) and named (STB) plot style tables. A complete plot setup pairs a PC3 with a plot style table: one says where to print, the other says how the linework should look.

This separation is deliberate and useful. You can send the same drawing to different devices by swapping the PC3 while keeping the same plot style, or change the printed appearance by swapping the plot style while keeping the device. Page setups, often saved in a template, bundle a PC3 and a plot style together so that selecting one page setup configures both halves of the plot in a single step.

Where PC3 files live and how to manage them

AutoCAD keeps PC3 files in a Plotters folder under your user profile, and the Plot Style folder holds the CTB and STB tables alongside. You can find the exact location through the Plotter Manager, which opens that folder directly. Knowing where they sit matters when you want to copy a configuration to another machine or back up your office's standard plotters and styles.

To share a setup, copy the PC3 (and any matching plot style table) into the corresponding folder on the other computer, and it appears in that machine's device list. Storing approved PC3 and plot style files centrally and distributing them is how a team gets consistent output — every drawing plots to the same devices, on the same papers, with the same line appearance, regardless of who pressed print.

Free download

Browse the full library — DWG & DXF, no signup.

Download CAD blocks

Questions

Frequently asked

What is a PC3 file used for?+

It is a saved plotter configuration that stores the output device, paper sizes and device-specific print settings, so you can set up plotting once and reselect it whenever you print. It covers both physical printers and virtual plotters like the DWG-to-PDF output.

How do I create a PC3 file?+

Open the Plotter Manager (via the Plot dialog or PLOTTERMANAGER) and run the Add-A-Plotter wizard. Choose the device or driver, name the configuration, and AutoCAD writes a new PC3 you can then edit to add custom paper sizes or adjust device options.

What is the difference between a PC3 and a plot style?+

A PC3 controls the device and paper — where and on what you print. A plot style table (CTB or STB) controls how objects look on the page, such as line colours and weights. A full plot setup pairs the two, often bundled together in a page setup.

Is DWG-to-PDF a PC3 file?+

Yes. The DWG-to-PDF output is produced by a virtual plotter defined in a PC3 configuration. So every time you publish a drawing to PDF from AutoCAD, you are plotting to a PC3 — it just writes a file instead of printing on paper.

Related downloads