Why AutoCAD Lineweights Are Not Showing on Screen (and How to Fix It)

You assigned lineweights to your layers, your PDF output looks correct, but every line on screen still appears thin and identical.

In most cases, the cause is LWDISPLAY being turned off, a display scale setting that is too low, incorrect layer assignments, viewport settings, Xref overrides, graphics configuration issues, or objects using the Default lineweight setting.

This guide walks through every known cause and the exact steps to fix it.

Quick Answer

If AutoCAD lineweights are not showing on screen:

• Turn on LWDISPLAY
• Enable Display Lineweight
• Increase the display scale
• Verify layer and object lineweights
• Check the LWDEFAULT variable
• Review viewport and layout settings
• Check for Xref overrides
• Verify the object is not using a polyline Global Width instead of a lineweight

For most users, enabling LWDISPLAY solves the problem immediately.

Understanding How AutoCAD Displays Lineweights

Before troubleshooting, it helps to understand what controls lineweight appearance.

There are two separate systems:

Screen Display

Controlled by:

• LWDISPLAY
• Display scale
• Graphics settings
• Visual styles

Printed Output

Controlled by:

• Object lineweights
• Layer lineweights
• CTB files
• STB files
• Plot settings

A drawing can print perfectly while still displaying thin lines on screen.

Fix 1: Turn On LWDISPLAY

This is the most common cause.

Method 1 — Command Line

Type LWDISPLAY → Press Enter → Type 1 → Press Enter.

Method 2 — Status Bar Toggle

• Look at the status bar.
• Find the Lineweight button.
• Click it to enable lineweight display.

When enabled, the icon becomes highlighted.

If the Lineweight Button Is Missing

• Click the Customization icon at the far right of the status bar.
• Enable Lineweight.
• Click the Lineweight button again.

Fix 2: Enable Display Lineweight and Increase Display Scale

Even when LWDISPLAY is active, lineweights may still appear identical if the display scale is too low.

Adjust the Display Scale

Type LWEIGHT → Press Enter.

In the Lineweight Settings dialog:

• Enable Display Lineweight
• Increase the Display Scale slider
• Click OK

The display scale only affects screen appearance.

It does not affect plotting or PDF output.

Fix 3: Verify the Actual Lineweight Values

Some lineweights are naturally difficult to distinguish on high-resolution monitors.

Typical visibility differences:

If most of your layers use 0.05 mm or 0.09 mm, the differences may be difficult to see.

Fix 4: Check the LWDEFAULT Variable

Many users overlook LWDEFAULT.

Whenever an object or layer is assigned Default lineweight, AutoCAD uses the value stored in LWDEFAULT.

The factory value is:

25

which equals:

0.25 mm

Verify LWDEFAULT

Type LWDEFAULT → Press Enter.

If the value has been changed to something very small, such as:

5

all objects using Default lineweight will appear much thinner than expected.

For most workflows:

25

is the recommended value.

Fix 5: Verify Layer Lineweights

Objects often inherit their lineweight from their layer.

Check Layer Settings

Type LA → Press Enter.

Then:

• Locate the object’s layer
• Review the Lineweight column
• Verify the layer is assigned the expected value

If the layer uses Default, refer to the previous section and verify LWDEFAULT.

Fix 6: Check Object-Level Overrides

Objects can override the layer settings.

Verify Object Properties

• Select the object
• Press CTRL+1
• Review the Lineweight property

For standard drafting workflows, the lineweight should usually be:

ByLayer

If the object is set to 0.00 mm, Default, or another override value, it may not match the layer settings.

Fix 7: Check for Polyline Global Width

This is one of the most misunderstood lineweight issues in AutoCAD.

A polyline can have a Global Width property.

When a polyline has a Global Width greater than zero, AutoCAD displays the physical width of the polyline rather than relying on lineweight display.

As a result:

• The polyline may appear thick even when LWDISPLAY is off.
• Changing lineweights may appear to have no effect.
• Users often assume lineweight display is broken.

Verify Global Width

• Select the polyline
• Open Properties (CTRL+1)
• Locate Global Width

If the value is greater than:

0

the polyline is using width instead of traditional lineweight display.

Fix 8: Understand the Zoom Effect

Lineweights are displayed using screen pixels.

Depending on your zoom level:

• Thin lineweights may appear identical
• Differences may become less visible
• Display thickness can seem inconsistent

Quick Test

Create several lines using:

• 0.09 mm
• 0.18 mm
• 0.25 mm
• 0.50 mm
• 0.70 mm

Zoom in and out.

The visual difference will change depending on the current view scale.

Fix 9: Verify Layout and Plot Style Settings

Layout tabs can display lineweights differently from Model Space.

Check the Page Setup

Right-click the Layout tab → Select Page Setup Manager → Click Modify.

Verify:

• Plot object lineweights is enabled
• Display plot styles is enabled

Then save the page setup.

Important CTB/STB Note

In Model Space, CTB and STB files generally do not control lineweight display.

In Layout (Paper Space), the situation is different.

When Display Plot Styles is enabled:

• CTB lineweights can be displayed on screen
• STB lineweights can be displayed on screen
• Layout appearance can closely match printed output

This explains why a drawing may look different in Model Space and Paper Space.

Fix 10: Verify Viewport Visual Style

Modern AutoCAD versions include several visual styles.

Lineweight behavior can vary depending on the selected style.

Recommended Visual Styles

Inside the viewport:

Type VSCURRENT → Press Enter.

Verify the style is:

• 2D Wireframe
• Fast 2D (newer AutoCAD versions)

Both styles properly support lineweight display.

Avoid Standard 3D Wireframe

The visual style called Wireframe (3D) behaves differently.

In some situations:

• Lineweights become difficult to distinguish
• Thickness appears inconsistent
• Display quality changes with zoom level

If you are troubleshooting lineweight display, switch to 2D Wireframe or Fast 2D first.

Fix 11: Check Block Behavior

Blocks can prevent expected lineweight behavior.

Common causes include:

• Geometry assigned fixed lineweights
• Geometry not using ByLayer
• Geometry not created on Layer 0

Recommended Block Standards

For reusable blocks:

• Create geometry on Layer 0
• Use ByLayer color
• Use ByLayer lineweight
• Avoid fixed object overrides

This allows blocks to inherit properties from the insertion layer.

Fix 12: Check External References (Xrefs)

External references can introduce hidden lineweight overrides.

Review Xref Layers

Type XREF → Press Enter.

Then:

• Review attached references
• Check layer overrides
• Verify inherited lineweights

Check VISRETAIN

Type VISRETAIN → Press Enter.

Recommended value:

1

This preserves layer overrides inside the host drawing.

Check XREFOVERRIDE

Type XREFOVERRIDE → Press Enter.

Review whether external reference properties are being overridden.

Fix 13: Test Hardware Acceleration

Graphics drivers occasionally interfere with lineweight rendering.

Disable Hardware Acceleration

Type GRAPHICSCONFIG → Press Enter.

Then:

• Turn off Hardware Acceleration
• Click OK
• Review the drawing

If the problem disappears, update the graphics driver and re-enable acceleration.

Fix 14: Regenerate the Drawing

Sometimes the display cache simply needs to be rebuilt.

Commands to Try

Type:

REGEN

or

REGENALL

Both commands force AutoCAD to redraw visible geometry.

AutoCAD for Mac

The same issue occurs on macOS.

Enable LWDISPLAY

Type LWDISPLAY → Press Enter → Type 1 → Press Enter.

Verify Mac Display Preferences

Open:

AutoCAD Menu → Preferences → Application → Look & Feel

Verify that:

Display Lineweight

is enabled.

Preventing Future Lineweight Problems

To avoid repeating this troubleshooting process:

• Save templates with LWDISPLAY enabled
• Standardize layer lineweights
• Use ByLayer whenever possible
• Build blocks using Layer 0
• Audit Xref overrides regularly
• Keep graphics drivers current
• Maintain consistent CTB/STB standards
• Verify LWDEFAULT has not been modified

Quick Troubleshooting Table

FAQ

Why do lineweights print correctly but not show on screen?

Because screen display is controlled by LWDISPLAY, while plotting is controlled by lineweights, CTB/STB files, and plot settings.

Why are all lineweights looking the same?

The most common causes are:

• LWDISPLAY is off
• Display Scale is too low
• Lineweights are extremely small
• The current visual style is not suitable

Why do lineweights appear in Layout but not in Model Space?

Layout tabs can display CTB/STB plot styles when Display Plot Styles is enabled.

Model Space does not normally use CTB/STB display simulation.

Does CTB affect lineweight display?

Not usually in Model Space.

In Layout tabs, CTB lineweights can appear on screen when Display Plot Styles is enabled.

Why do my blocks ignore layer lineweights?

The geometry inside the block may have fixed lineweights assigned instead of using ByLayer properties.

Why does changing lineweight not affect my polyline?

The polyline may be using Global Width. When Global Width is greater than zero, AutoCAD displays the width of the polyline rather than the lineweight setting.

What is the default value of LWDEFAULT?

The factory value is:

25

which corresponds to:

0.25 mm