Square and Rectangle Symbols

The square is one of the most fundamental geometric shapes in typography and design, and Unicode provides a comprehensive set of square characters ranging from simple filled and outlined squares to squared Latin letters, CJK squared characters, and mathematical square operators. This guide catalogs every major square symbol in Unicode, explains the blocks where they reside, and provides practical guidance for using them in documents, terminals, and web applications.

Basic Square Shapes

The Geometric Shapes block (U+25A0-U+25FF) is the primary home for square characters:

Square Sizes Compared

Unicode provides squares in multiple sizes to accommodate different typographic needs:

Squares with Special Fills

The Geometric Shapes block also provides squares with various internal patterns:

These patterned squares are useful for creating legends in charts, representing different categories in plain-text diagrams, or indicating texture in technical documentation.

Squared Latin Letters

Unicode provides squared (boxed) versions of Latin letters in the Enclosed Alphanumerics and Enclosed Alphanumeric Supplement blocks:

Squared Uppercase Letters (Negative/Filled)

The range U+1F170-U+1F189 in the Enclosed Alphanumeric Supplement block contains negative squared (white letter on filled square) versions:

Some of these have become well-known emoji:

Squared CJK Ideographs

The Enclosed CJK Letters and Months block (U+3200-U+32FF) and Enclosed Ideographic Supplement (U+1F200-U+1F2FF) contain squared CJK characters:

These squared CJK characters are commonly used in Japanese signage, TV broadcasts, and digital interfaces to indicate business status, transportation information, and regulatory notices.

Mathematical Square Operators

The Mathematical Operators block includes square-shaped operators:

These are used in specialized mathematical notation where squared operators have distinct semantics from their circled counterparts (⊕, ⊖, ⊗, ⊙).

Checkbox and Ballot Squares

Squares serve as checkboxes and ballot marks in forms and documents:

The ballot box characters (☐ ☑ ☒) are especially useful for creating checklists in plain text:

☐ Buy groceries
☑ Write report
☒ Cancel subscription
☐ Schedule meeting

Squares in Terminal UI

Squares and rectangles are commonly used in terminal applications for:

Progress Bars

Loading: ■■■■■■■■□□□□□□□ 53%
         ▓▓▓▓▓▓▓▓░░░░░░░ 53%

Color Swatches (with Emoji)

🟥 Red      🟧 Orange   🟨 Yellow
🟩 Green    🟦 Blue     🟪 Purple
🟫 Brown    ⬛ Black    ⬜ White

Grid-Based Displays

■ □ ■ □ ■
□ ■ □ ■ □
■ □ ■ □ ■
□ ■ □ ■ □

Emoji Squares

Modern Unicode includes colored square emoji:

These colored squares are widely used for creating simple pixel art, color palettes, status indicators, and heat maps in messaging applications.

Combining Enclosing Square

Similar to the combining enclosing circle, Unicode provides:

Placing U+20DE after a character encloses it in a square. However, as with the enclosing circle, font support is inconsistent. Precomposed squared characters are preferred when available.

Working with Square Characters in Python

import unicodedata

# Enumerate various square characters
squares = {
    "filled": "\u25A0\u25AA\u25FC\u25FE\u2B1B",
    "outlined": "\u25A1\u25AB\u25FB\u25FD\u2B1C",
    "patterned": "\u25A4\u25A5\u25A6\u25A7\u25A8\u25A9",
    "ballot": "\u2610\u2611\u2612",
}

for category, chars in squares.items():
    print(f"\n{category}:")
    for char in chars:
        name = unicodedata.name(char, "UNKNOWN")
        print(f"  {char}  U+{ord(char):04X}  {name}")

# Create a simple checklist
tasks = [
    ("Buy groceries", False),
    ("Write report", True),
    ("Cancel subscription", None),  # rejected
]

for task, status in tasks:
    if status is None:
        mark = "\u2612"   # ballot box with X
    elif status:
        mark = "\u2611"   # ballot box with check
    else:
        mark = "\u2610"   # empty ballot box
    print(f"{mark} {task}")

Practical Use Cases

Summary

Unicode offers an extensive collection of square-based characters that serve geometric, typographic, mathematical, and pictographic purposes. From the basic filled and outlined squares through patterned variants, checkboxes, squared letters, mathematical operators, and colored emoji, squares are among the most versatile and frequently used symbol shapes in Unicode. Understanding the full range of available square characters helps developers and designers choose the semantically correct character for any context, whether building terminal UIs, writing mathematical notation, or creating visual indicators in plain text.