Multi-Screen Alignment

Compare visible alignment and relative color across two or more displays using browser guides.

Go to test controls

This check runs directly on this page without requiring fullscreen. Review what this browser test can and cannot measure.

Before you start

  • For alignment, resize one ordinary browser window across the extended displays so a continuous line crosses their boundary.
  • Keep zoom, room lighting, and picture settings fixed for the first comparison. Optional fullscreen covers one display; separate windows are suitable for same-color comparison.
Step-by-step instructions

How to run this check

  1. Start Multi-Screen Alignment in its ordinary browser-window mode
  2. Resize one window across the extended displays and use a continuous horizontal line for side-by-side screens or vertical line for stacked screens
  3. Record the boundary offset before changing one arrangement, scaling, or physical-position setting
  4. For color comparison, use the same color in the spanning window or separate windows; optional fullscreen covers one display
  5. Save the alignment and color observations separately, including not assessed where appropriate, with the actual pattern and setup

Put one unchanged pattern across the display boundary

  1. Use an extended desktop, restore the browser to a resizable window, and drag it across the two displays. Start a pattern below; it stays inside that window.
  2. For side-by-side displays, compare the horizontal line as it crosses the boundary. For vertically stacked displays, compare the vertical line. Note which side is higher or offset before changing either physical placement or the OS arrangement.
  3. Use the same solid color on both parts of the window for a relative color comparison. Keep the viewing position and lighting fixed. If the OS prevents a spanning window, use one browser window on each display with the same named color; independent centered lines are not a continuous alignment reference.
  4. Change one setting, then restore it to see whether the difference returns. Save which displays, setting, direction, and color were involved. This page cannot detect your display arrangement.

Fullscreen is optional for inspecting one display. Return to the window with the fullscreen button to continue the spanning comparison.

What each pattern can show

Edge alignment

Shows a visible break where a line crosses display edges. Physical height, tilt, bezel width, and operating-system arrangement remain separate variables.

Color matching

Supports a relative same-pattern comparison under shared room lighting. It does not measure luminance, white point, gamut coverage, or Delta E.

Grid overlay

Provides several crossing points for checking visible scale, rotation, and continuity. Exact bezel compensation still requires physical measurements and GPU settings.

Compare one reversible setting at a time

Photograph or note the same pattern before each change. Keep the browser window, browser zoom, room lighting, viewing angle, and physical display position fixed unless that is the variable being checked.

Change Keep fixed Recheck Boundary
OS scaling Resolution, browser zoom, display preset Apparent text/UI size and window transition between displays Shows the combined OS and app behavior, not physical pixel density by itself
Resolution Scaling, browser zoom, preset, physical placement Grid scale and edge continuity The browser cannot confirm the panel's native resolution or scaling hardware
Refresh rate Resolution, scaling, preset, test content Motion on the target display; use the Refresh Rate Test for callback cadence A visual change does not isolate the GPU, compositor, cable, or panel
Display preset Pattern, room lighting, viewing angle, OS profile Relative brightness and warm/cool appearance Exact luminance and color matching require a calibrated meter

No pattern opened in this visit. Record only observations you actually made.

What this browser test can tell you

Can help you check

  • Visual alignment and relative color comparison between screens.

Cannot measure

  • This test cannot provide calibrated color matching or physical bezel measurement.

Interpret this observation

  • Record alignment and color appearance separately, including not assessed. Save the actual pattern, window dimensions, and setup before changing one physical or OS setting.
  • Optional native fullscreen covers one display. Separate windows can compare the same color, but independently centered lines are not one continuous alignment reference.
  • Exact matching and dimensions require a calibrated colorimeter plus a physical measuring tool.
Setup and sources

Recommended setup

  1. Resize one ordinary browser window across extended displays for a continuous alignment line. Use a horizontal line for side-by-side screens and a vertical line for stacked screens.
  2. View the screens from your normal position under steady room lighting.

Sources

Methodology reviewed: