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How to Display a Horizontal Bar Chart in Batch Script

While Batch scripts are primarily used for text processing and automation, you can also use them to create simple, impactful data visualizations. A Horizontal Bar Chart is an excellent way to display disk usage, progress percentages, or comparative statistics (like CPU load) directly in the console without needing a GUI.

In this guide, we will demonstrate how to build a dynamic bar chart using string repetition and ANSI characters.

The Basic Concept​

To create a bar chart, we take a numeric value (e.g., 75%) and convert it into a string of symbols (e.g., 37 blocks if scaled to half-width). We then print that string next to a label.

The Padding Loop​

Because Batch does not have a "repeat character" function, we use a FOR /L loop to append a block character to a variable until it reaches the desired length.

Method 1: The Simple ASCII Bar​

This version uses standard characters (like #) and works on all versions of Windows.

Implementation Script​

@echo off
setlocal enabledelayedexpansion

:: Maximum bar width in characters (prevents bars from exceeding terminal width)
set "maxBarWidth=50"

:: Space padding for label alignment (must be at least as wide as the longest label)
set "labelPad=               "

:: Define the "data" for our chart (Label:Value as percentage)
set "items=Sales:40 Marketing:75 Support:20 Engineering:60"

echo PERFORMANCE DASHBOARD
echo ------------------------------------------

for %%A in (%items%) do (
    for /F "tokens=1,2 delims=:" %%a in ("%%A") do (
        set "label=%%a!labelPad!"
        set "val=%%b"

        :: Scale value to fit within terminal width
        :: Maps 0-100%% to 0-maxBarWidth characters
        set /a "barLen=(val * maxBarWidth) / 100"

        :: Generate the bar string
        set "bar="
        for /L %%i in (1,1,!barLen!) do set "bar=!bar!#"

        :: Print padded label and bar
        echo !label:~0,15! !bar! ^(!val!%%^)
    )
)

echo ------------------------------------------

endlocal
pause

Method 2: The Modern ANSI Block Chart (Cleanest)​

On Windows 10 and 11, we can use the "Full Block" character (█) and ANSI colors to create a much more professional-looking chart.

@echo off
setlocal enabledelayedexpansion

set "labelPad=          "
set "disks=C:85 D:45 E:12"

echo DISK CAPACITY MONITOR
echo.

for %%A in (%disks%) do (
    for /F "tokens=1,2 delims=:" %%D in ("%%A") do (
        set "name=%%D!labelPad!"
        set "used=%%E"

        :: Scale: divide by 2 to keep bars within terminal width
        set /a barWidth=used / 2

        set "bar="
        for /L %%i in (1,1,!barWidth!) do set "bar=!bar!█"

        echo !name:~0,5! [!bar!] !used! GB
    )
)

endlocal
pause

Creating a Relative "Progress Bar"​

Sometimes you want the bar to be a fixed width (e.g., 20 blocks wide) and show progress within that frame.

@echo off
setlocal enabledelayedexpansion

set "current=150"
set "total=200"
set "barWidth=20"

:: Calculate percentage
set /a "pct=(current * 100) / total"

:: Calculate how many of the blocks should be filled
set /a "fill=(pct * barWidth) / 100"
set /a "empty=barWidth - fill"

set "bar="
for /L %%i in (1,1,%fill%) do set "bar=!bar!█"
for /L %%i in (1,1,%empty%) do set "bar=!bar!░"

echo Progress: [!bar!] %pct%%%

endlocal
pause

Key Components:​

  • █ (Alt+219): The solid block character for the filled portion.
  • ░ (Alt+176): The light shaded block for the empty portion.
  • Scaling: If your data values are very high (like 1000), divide them by a factor (like 10 or 50) so the bar doesn't wrap to the next line.
Note on special characters

The █ and ░ characters are from the OEM character set (code page 437) used by cmd.exe by default. If your batch file is saved with a different encoding, these characters may not display correctly. Most Windows text editors save .bat files in the correct encoding automatically.

Creating Borders and Headers​

To make your table look truly professional, surround it with ASCII borders.

@echo off
setlocal enabledelayedexpansion

set "labelPad=                              "

echo +----------------------+------------+
echo ^| NAME                 ^| STATUS     ^|
echo +----------------------+------------+

set "n1=System Check!labelPad!"
set "n2=Database Sync!labelPad!"

set "s1=ONLINE!labelPad!"
set "s2=OFFLINE!labelPad!"

echo ^| !n1:~0,20! ^| !s1:~0,10! ^|
echo ^| !n2:~0,20! ^| !s2:~0,10! ^|
echo +----------------------+------------+

endlocal
pause

Best Practices​

  1. Label Alignment: Use the fixed-width padding trick (appending spaces and taking a substring) to ensure the start of every bar lines up vertically.
  2. Scale to Fit: Always scale your bar lengths relative to the terminal width. A maxBarWidth of 40–50 characters leaves room for labels and values on an 80-column terminal.
  3. Color Coding: Use Red for "Danger" levels (e.g., Disk > 90%) and Green for "Safe" levels.
  4. Handle Zeros: If a value is 0, for /L %%i in (1,1,0) simply does not iterate, leaving the bar empty. This is correct behavior, but consider printing a placeholder like [empty] if a completely blank bar might confuse users.

Conclusion​

Horizontal bar charts are a powerful way to add a layer of visual intelligence to your Batch scripts. Instead of forcing a user to read through numbers, you can show them exactly where the bottlenecks or capacity issues are at a single glance. With a few simple loops and ANSI blocks, your command-line tools can provide dashboard-level insights with zero external dependencies.

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