AutoCAD Plot to Scale: Print an A3 PDF at 1:100 in 9 Steps (2026)

An example from a drafting desk: a civil engineering student finishes a ground floor plan, clicks Plot, picks Fit to Paper and sends the PDF to a print shop in Abbottabad. The supervisor lays a scale ruler on the A3 print, and nothing measures right. The fix is to learn the AutoCAD plot to scale method once: set up a layout at 1:1, give the viewport a real scale such as 1:100, and plot the layout. It takes about ten minutes the first time and two minutes after that.

This guide walks through that method with metric and feet-and-inch examples. Here is what you'll be able to do after reading it:

• Explain the difference between plot scale, layout scale and viewport scale
• Work out which sheet size a plan needs before you open the Plot dialog
• Produce an A3 PDF at 1:100 that measures correctly with a scale ruler
• Choose between a CTB and an STB plot style table for black-and-white prints
• Diagnose the usual reasons a PDF comes out the wrong size

What Does "Plot to Scale" Mean in AutoCAD?

In AutoCAD you draw real objects at their real size. A 4,500 mm wall is drawn 4,500 units long, not shrunk to fit a page. Scaling only happens at the output stage, when AutoCAD maps drawing units onto paper millimeters or inches.

Autodesk's help page About Setting the Plot Scale describes the ratio plainly. If your paper is in millimeters and you enter 1 mm = 10 units, each printed millimeter stands for 10 real millimeters. That is a 1:10 drawing.

A scale of 1:100 therefore means one millimeter on paper equals 100 mm in the building. A 10 m room prints 100 mm long. Anyone with a scale ruler can check your sheet, and that is the whole point of a scaled drawing.

Fit to Paper does something different. It makes the drawing as large as the sheet allows, so the ratio becomes an odd number that no scale ruler matches. Autodesk suggests it for drafts where precise scale matters less. That's fine for a check print, but not for a sheet someone will measure.

Model Space or Layout: Where Should You Plot From?

You can plot from either, but they behave differently.

Model space plotting uses one scale, typed into the Plot dialog. It works for a quick single view. The trouble starts when you need a title block, notes and two views at different scales on one sheet.

Layout plotting uses two scales, as Autodesk's plot scale page explains. The layout itself is plotted at 1:1 because it already represents the paper. Inside it, each viewport has its own model scale. Your title block, sheet border and general notes sit on the layout at their printed size, and the floor plan shows through a viewport at 1:100.

For any drawing you'll submit, hand to a contractor or put in a portfolio, use a layout. Every AutoCAD plot to scale job in the rest of this guide assumes you do.

Paper Sizes and the Scale Math to Do First

Most plotting problems start with the wrong sheet, so check the fit before touching any settings. The A-series sizes are fixed by ISO 216. Markus Kuhn's reference page on ISO paper sizes lists them: A0 is 841 × 1189 mm with an area of one square meter, and each smaller size has half the area of the one before it.

Now divide the building size by the scale. Take a footprint of 12 m × 20 m:

• At 1:100 it prints 120 × 200 mm. That fits on an A3 sheet with its long side across (420 × 297 mm) with plenty of room for a title block and notes.
• At 1:50 it prints 240 × 400 mm. That technically squeezes onto A3, but leaves no space for a border or title block. Move up to A2.

The table below shows how one meter of building prints at common metric scales. Keep it next to your keyboard until the numbers become automatic.

The third column explains a common surprise. Text written in model space at 2.5 mm height disappears on a 1:100 print, because it shrinks a hundred times. Either multiply text height by the scale, or use annotative text, which Autodesk says is sized by the current annotation scale so it prints correctly.

AutoCAD Plot to Scale: The 9-Step Method

The AutoCAD plot to scale steps below use a metric plan drawn in millimeters and an A3 PDF. The command names are the same in AutoCAD and AutoCAD LT.

Step 1: Confirm Your Drawing Units

Type UNITS and check the insertion scale. Then measure one known item with DIST. If a 1,200 mm window measures 1.2, you drew in meters, and every scale in this guide changes by a factor of 1,000. Fix the units decision before plotting, not after.

Step 2: Open a Layout Tab and the Page Setup Manager

Click the Layout1 tab, right-click it and rename it to something useful, such as GF-PLAN. Then type PAGESETUP and click Modify. Settings saved here stay with the layout, so you won't repeat them on the next print.

Step 3: Pick a PDF Driver and Paper Size

Under Printer/plotter, choose a PDF configuration. Autodesk's PDF export page lists four AutoCAD PDF presets. High Quality Print suits drawings headed for paper. Smallest File suits email. Web and Mobile keeps hyperlinks working. General Documentation covers most other uses. Then select an ISO A3 paper size of 420 × 297 mm and set the orientation to Landscape.

Step 4: Choose Layout as the Plot Area at 1:1

Plot area should read Layout. Set the scale to 1 mm = 1 unit. Fit to Paper is greyed out when Plot Area is Layout, according to Autodesk's plot scale page, and that's a useful safety catch. The layout is the paper, so it always plots at 1:1.

Step 5: Choose the Plot Style Table and Lineweights

Pick a plot style table under Plot style table (pen assignments). For black-and-white prints, a monochrome CTB is the usual choice. Under Plot options, keep Plot with plot styles ticked. The Page Setup dialog reference notes that this option also turns on Plot object lineweights. Click OK and close the manager.

Step 6: Insert a Title Block and Draw the Viewport

Draw or insert your border and title block on the layout at real paper size. An A3 border might sit 10 mm inside the sheet edge. Delete the default viewport if it's in the wrong place, then use MVIEW to draw a new rectangle inside the border. Put viewports on their own layer, such as VPORT, and set that layer to No Plot so the frame doesn't print.

Step 7: Give the Viewport an Exact Scale

Select the viewport border and pick 1:100 from the Viewport Scale list on the status bar. You can do the same through the Properties palette or the triangular scale grip. A keyboard option also works: double-click inside the viewport, type ZOOM, then 1/100XP. Autodesk's page About Scaling Views in Layout Viewports lists all four methods and adds one detail: stretching the viewport border never changes the scale.

Step 8: Pan Into Position and Lock the Viewport

While inside the viewport, use PAN only, never the mouse wheel, to center the plan. Then double-click outside the viewport, select its border and click the Viewport Lock button on the status bar. A locked viewport can't change scale through an accidental zoom, and that's a frequent way a correct sheet goes wrong the night before a deadline.

Step 9: Preview, Plot and Measure the PDF

Type PLOT, confirm the page setup name, click Preview and check that nothing is clipped. Save the PDF. Then open it, find a known dimension such as a 5,000 mm wall and measure it with your PDF reader's measuring tool or a ruler on a printed copy. At 1:100 it should read 50 mm. If it does, your sheet is correct.

Which Plot Style Table Should You Use: CTB or STB?

A plot style table decides how each object prints: its color, lineweight and screening. Autodesk's About Plot Style Tables page describes two kinds.

Start with a CTB. It's simple and most drawings you receive from others will expect one. One warning from an Autodesk support article: objects given a True Color (RGB) value can still print in color under a monochrome CTB, because a CTB only maps the 256 index colors. If a few lines come out blue on your "black" PDF, check their color for an RGB value and switch it to an index color.

Feet-and-Inch Drawings: Using Imperial Scales Correctly

If your plans are dimensioned in feet and inches, the method stays the same, but you pick imperial scales. Two common ones are 1/8" = 1'-0", which equals 1:96, and 1/4" = 1'-0", which equals 1:48. The math is simple: one foot is 12 inches, so 1/8 inch per foot is 1 to 96.

Here is a worked case. A plot of 35 ft × 65 ft at 1/8" = 1'-0" prints about 4.4 × 8.1 inches, roughly 111 × 206 mm. That fits on A3 with space left for a schedule.

The trap is mixing units. When the model is drawn in inches, keep the page setup paper units in inches as well, so the imperial entries in the viewport scale list mean what they say. A model drawn in inches viewed through a 1:96 viewport on a millimeter layout prints 25.4 times too small.

Line Types and Text That Look Wrong After Scaling

Dashed and center lines often print as solid lines on a scaled viewport. The system variable PSLTSCALE controls this. Autodesk's PSLTSCALE reference says that at its default value of 1, dash lengths in viewports follow paper space units, so viewports at different scales show identical dashes. LTSCALE still adjusts the overall dash length.

After changing either value, type REGENALL. The page notes that existing viewports don't refresh on their own, which is why the change can look like it failed.

For text and dimensions, choose one approach per drawing. Either scale them by hand using the table earlier, or use annotative styles and set the annotation scale to match the viewport. Mixing both methods on one sheet leads to tiny notes beside oversized dimensions.

Plotting a Full Set of Sheets to One PDF

A house drawing set usually has a site plan, floor plans, elevations and a section. Plotting each layout separately creates a folder full of files. Autodesk's PDF export page describes two better commands:

1. EXPORTPDF exports all layouts of the current drawing to one PDF.
2. PUBLISH lets you choose specific layouts, including layouts from several DWG files, and combine them into one multi-sheet PDF.

Each layout uses its own saved page setup, so the work you did in Steps 2 to 5 pays off here. Clear layout tab names also make the sheet list easier to check before you publish.

Why Does My PDF Print at the Wrong Size?

When an AutoCAD plot to scale attempt doesn't measure correctly, the cause is usually one of these.

One more check catches printing problems outside AutoCAD. When you send the PDF to a print shop, ask them to print at actual size, not "fit to page". A PDF reader set to shrink pages to fit printer margins will quietly break a perfect 1:100.

Practice Plotting in PSTA's AutoCAD Course

Plotting is listed as a learning outcome in PSTA's AutoCAD course (2D, 3D and BIM), which covers plotting, printing and publishing drawings to scale for construction use. The ten modules move from interface setup and 2D drafting through layers, dimensions, blocks and X-Refs, isometric drawing, 3D modeling, BIM basics and rendering, and end with a final architectural or mechanical project.

According to the course page, the program runs 45 to 90 days at beginner level, with a listed fee of Rs. 28,000 when this guide was written. You can study on the Abbottabad campus, take the classes online, or combine the two. Fees and batch dates can change, so check the course page or compare all PSTA courses before you decide.

If you want more practice first, draw the 5 Marla plan from our house plan in AutoCAD walkthrough and plot it with the steps above. Our AutoCAD shortcut keys list will speed up the drafting part, and students can check eligibility for Autodesk's education license in the AutoCAD free for students checklist. If electrical panel layouts are your goal, the industrial automation course pairs well with drafting skills.

Measure Your Last PDF Today

Open the last PDF you plotted from AutoCAD and measure one dimension you know. If it matches the scale on your title block, you already have a working setup, so save it as a page setup and reuse it. If it doesn't, follow the nine steps on that same drawing tonight. For guided lessons, see how enrollment works on the admission page, or ask the PSTA office about batch timings through WhatsApp at +92 314 5424399.