How to draw a rectangle in AutoCAD: the REC command, eight options and three reasons it lands wrong

How to draw a rectangle in AutoCAD comes down to RECTANG, aliased REC. Almost everyone knows how to call it, and yet it produces more "why did it come out wrong" questions than any other drawing command.

The reason is that it carries eight options split across two prompts, and four of them persist into later rectangles. To learn modelling and documentation end to end, see the AutoCAD for construction course.

The REC command in AutoCAD: two prompts, eight options

The button sits on the Draw panel of the Home tab, sharing a flyout with Polygon.

Type REC and press Enter. The command asks exactly twice, and each prompt opens a different group of options.

The split makes sense. The five at the first prompt change the shape of the rectangle about to be drawn. The three at the second prompt change how you state the remaining corner.

Read that way, how to draw a rectangle in AutoCAD is mostly a question of which prompt you are standing at. Options typed at the wrong one are simply refused, which is why the command sometimes seems to ignore a letter you are sure you typed.

The result is not four separate lines. The Autodesk reference states the command "creates a closed rectangular polyline" — see the RECTANG (Command) page.

Drawing to exact drawing-set dimensions

Most people type relative coordinates, but the Dimensions option is the surer route. It asks for a length and a width directly, so there is no sign convention left to get wrong.

Try it on a 3600 by 2400 column bay:

1. Type REC and Enter. Pick the first corner, or snap to an existing point.
2. Type D and Enter. The command asks Specify length for rectangles <10.0000>:, so type 3600.
3. It then asks Specify width for rectangles <10.0000>:, so type 2400.
4. It returns to asking for the other corner. Move the cursor to the side you want the rectangle on, then click.

Step four is the one that decides things. The size was settled in steps two and three, so the final click only chooses which side of the first corner the rectangle sits on.

To snap accurately onto a wall corner or a grid intersection, object snap has to be on — see Object snap in AutoCAD.

The signs of the two numbers decide where it lands

Typing relative coordinates is quicker, but one thing has to be clear: the same first corner and the same size give four different results depending on the signs.

The leading @ is not decoration. It marks the two numbers as relative to the corner just picked. Leave it out and they become absolute coordinates from the drawing origin, and the rectangle lands far away.

Draw a rectangle by area when only the area is fixed

The Area option is rarely used and fits early design work well. When the brief calls for an 18 square metre room but the proportions are open, give the area and one side, and the command works out the other.

1. Type REC and pick the first corner.
2. Type A and Enter. The command asks Enter area of rectangle in current units <100.0000>:.
3. Type the area. On a millimetre drawing, 18 square metres is 18000000.
4. It asks which side to calculate from, Length or Width, then asks for that side.

The rectangle appears with exactly the area you stated. It is a quick way to test a few plan options without reaching for a calculator each time.

Three real reasons a rectangle comes out wrong

This is the most common group of complaints, and it almost always reduces to the three causes below. None of them is a software fault.

One: the @ was left out. Typing 3600,2400 instead of @3600,2400 makes the numbers absolute. A rectangle still appears, but nowhere near where you clicked.

Two: dynamic input is set to the other format. The tooltip beside the cursor has its own system variable controlling whether it reads coordinates as relative or absolute, called DYNPICOORDS. You do not have to change the variable: type @ to force relative or # to force absolute, and each applies to that entry only. Autodesk describes it on the To Specify Relative or Absolute Coordinates in the Dynamic Input Tooltip page.

Three: an option is still remembered from last time. This is the hardest to spot, and it is what the next section is about.

A quick check for all three: call the command and read the first line before clicking. If any setting is active, the command prints something like Current rectangle modes: Chamfer=300.0000 x 300.0000 Rotation=30.

Four options that persist, and why that is the biggest trap

Chamfer, Fillet, Width and Rotation all keep their values after use. Set one and every later rectangle follows, until you reset it to zero.

The usual result: you draw a filleted rectangle for a worktop, then a column bay a few minutes later comes out with rounded corners too. Or you rotate one rectangle 30 degrees and every rectangle after it leans the same way for no apparent reason.

The fix is to reset the values, not to restart the program:

Rotation behaves differently from the other three: it is only accepted after the first corner has been picked. Type R at the opening prompt and the program answers Point or option keyword required. The correct sequence is on the To Draw a Rectangle page: pick the first corner, type R, give the angle, then pick the other corner.

Elevation and Thickness persist too, but they belong to 3D work. Leave them at zero for 2D documentation.

A rectangle is a closed polyline, so edit it like one

This opens up more than the options above suggest. A polyline is one object made of connected segments, and it can be closed — see the PLINE (Command) page.

What follows in practice:

• Select the rectangle and open the Properties palette with Ctrl and 1 to read both area and perimeter, with no measuring command needed.
• One click selects all four sides. To edit a single side, EXPLODE it into four separate lines first.
• OFFSET produces a concentric rectangle inside or outside it, which is exactly how a two-leaf wall gets drawn.
• PEDIT changes the line width of the whole shape, or joins further segments onto it.

A habit worth having on building drawings: column bays, floor panels and title blocks are all rectangles, so drawing them with REC means the floor area can be read straight from Properties. That is quicker than outlining the region and calling an area command.

Taken together, that is how to draw a rectangle in AutoCAD and keep it useful afterwards: state the size rather than eyeball it, read the first line before clicking, reset anything that persists, and remember the result is one polyline rather than four lines. Those four habits cover nearly every rectangle a drawing set needs.

Frequently asked questions

Which command draws a rectangle in AutoCAD?

RECTANG, aliased REC. The button is on the Draw panel of the Home tab, sharing a flyout with Polygon.

How do I draw one to an exact size?

Type REC, pick the first corner, type D, give the length and the width, then move the cursor to the side you want and click.

Why does the rectangle land in the wrong place when I type its size?

The @ was left out, so the numbers were read as absolute coordinates from the drawing origin. Type @3600,2400 rather than 3600,2400.

Why do my rectangles suddenly have rounded corners, or lean over?

Because Fillet or Rotation is still remembered from an earlier rectangle. Read the command's first line; if it shows Current rectangle modes, reset those values to zero.

Which command draws a square?

The same one. Type D and give an equal length and width, or type relative coordinates with two equal numbers such as @1200,1200.

How do I read the area of a rectangle I just drew?

Select it and open the Properties palette with Ctrl and 1. Because it is a closed polyline, the area and perimeter fields are right there.

Related articles

• How to draw a revision cloud in AutoCAD — converting a closed rectangle into a review cloud
• How to draw an arc in AutoCAD — eleven construction methods and the radius trap
• Object snap in AutoCAD — snapping to wall corners and grid intersections
• What is AutoCAD — a handbook for people working in construction