Pangu CJK Spacing Formatter

About this pangu cjk spacing formatter

Typographic Rationale and W3C CLREQ Standards

In professional typesetting across East Asian languages—including Traditional Chinese, Simplified Chinese, Japanese, and Korean—running Latin letters, numerals, or Western symbols directly adjacent to square CJK ideographs without spacing creates visual crowding and hampers readability. The W3C specification Requirements for Chinese Text Layout (CLREQ, §3.2.2) explicitly recommends inserting an aesthetic inter-script space—traditionally equivalent to a quarter of an em space (四分之一全角空格 / U+2005)—between Han characters and Western alphanumeric glyphs.

Because standard web browsers and plain-text editors lack native contextual kerning between CJK and Western fonts, web developers, technical writers, and publishers rely on algorithmic text formatters—commonly referred to as “Pangu spacing” (盘古之白)—to insert standard ASCII spaces at typographical boundaries.

Spacing Rules and Boundary Conditions

Effective CJK-Western spacing requires rigorous contextual boundary handling to prevent inappropriate space insertion around punctuation and code snippets:

• CJK and Latin Letters / Numerals: A single space is placed between any CJK ideograph (Unicode blocks U+4E00..U+9FFF, Hiragana U+3040..U+309F, and Katakana U+30A0..U+30FF) and preceding or succeeding Latin letters (A-Z, a-z) or Arabic numerals (0-9).
• Full-Width Punctuation Immunity: Full-width East Asian punctuation marks—such as ideographic commas (，), full stops (。), pause marks (、), and full-width colons (：)—already carry built-in typographic glyph whitespace. Inserting spaces adjacent to full-width punctuation is forbidden.
• Currency, Percentage, and Dimension Units: Suffix symbols like percentage signs (100%) and prefixed currency symbols ($50, ¥100) remain glued to their numerical quantities, preventing fragmented tokenization while maintaining proper spacing against adjacent ideographs.
• Markdown and Inline Code Protection: Text enclosed within inline backticks (`code`), HTML tags, or hyperlinked URLs is protected so technical tokens, file paths, and syntax delimiters are not mutated.

Algorithm Architecture: Deterministic State Machine vs. Regex

While simplistic formatters employ chained global regular expressions, complex documents with mixed markup can suffer from exponential regex backtracking or destroyed URL schemas. This formatter implements a high-throughput deterministic token scanner:

1. Token Classification: Every Unicode codepoint is classified into discrete character classes (CJK Ideograph, Latin Letter, ASCII Digit, Full-Width Punctuation, Half-Width Delimiter, or Whitespace).
2. Lookahead and Lookbehind Inspection: The scanner evaluates the boundary transition between adjacent tokens, applying CLREQ kerning predicates in a single linear pass (O(N) time complexity).
3. Idempotent Output Generation: Repeated formatting runs produce identical outputs, ensuring that running the tool multiple times never accumulates duplicate spaces.

Editorial and Publishing Workflows

Pangu text spacing is essential across technical documentation pipelines, software localization, marketing copy, and multi-language publishing. Open-source maintainers utilize automated spacing formatters in GitHub Actions and pre-commit hooks to standardize Markdown documentation, blog articles, and user manuals across global development teams.

Client-Side Privacy and Document Security

All text parsing, Unicode classification, and spacing adjustments take place 100% locally inside your browser memory. Whether formatting confidential internal memos, legal contract drafts, or pre-release press statements, no text payloads are transmitted over external networks or logged by remote servers.

Adds spaces only at adjacent U+3400–U+9FFF Han and ASCII alphanumeric boundaries, then collapses repeated horizontal spaces Applies Unicode-compliant text transformations and parsing directly in the browser tab without data leakage.

Text processing & transformation mechanics

Adds U+0020 only at adjacent U+3400–U+9FFF Han and ASCII alphanumeric boundaries, collapses repeated spaces or tabs, and trims the result.

Worked text manipulation example

Character encoding & string length boundaries

Only U+3400–U+9FFF Han and ASCII alphanumerics are handled; punctuation, other scripts and full typography rules are not.

Text formatting and transformations in Chinese-English Spacing Beautifier preserve character integrity. Check edge cases such as multi-line inputs and special characters before downstream use.

In-memory text processing boundary

String operations and Unicode manipulations in Chinese-English Spacing Beautifier execute entirely in local browser memory without transmitting input text.

Unicode Consortium & text formatting standards

Unicode Consortium standard annexes (UAX) and character encoding specifications:

• Implementation-specific Han–ASCII spacing algorithm (not a full Pangu rules implementation; no governing external standard)

Pangu CJK Spacing Formatter verification · Audit standards

How to use it

1. Paste or type your mixed CJK and Western text into the input editor.
2. Select desired spacing options (e.g., standard CLREQ quarter-em spaces, Markdown code block protection, or symbol isolation).
3. Observe the instant live formatted preview rendered in the output pane.
4. Click the Copy button to copy the professionally typeset text directly to your clipboard.