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How to Use the SymbolFYI HTML Entity Finder
A guide to SymbolFYI's HTML Entity Finder — search for HTML entities by name, character, or code point, with copy-ready entity codes for your web projects.
How to Use the SymbolFYI String Length Calculator
A guide to SymbolFYI's String Length Calculator — measure string length in characters, code points, UTF-8 bytes, UTF-16 code units, and grapheme clusters.
How to Use the SymbolFYI Text Diff Tool
Guide to SymbolFYI's Text Diff Tool — compare two texts character by character to find invisible Unicode differences, encoding issues, and confusables.
How to Use the SymbolFYI Fancy Text Generator
A guide to SymbolFYI's Fancy Text Generator — convert text to Unicode bold, italic, script, fraktur, and monospace styles for social media.
How to Use the SymbolFYI Symbol Table Tool
A complete guide to SymbolFYI's Symbol Table — browse characters by Unicode block, filter by category, copy characters, and explore encoding details.
How to Use the SymbolFYI Encoding Converter
A guide to SymbolFYI's Encoding Converter — convert characters between UTF-8, UTF-16, HTML entities, CSS escapes, and other formats instantly.
How to Use the SymbolFYI Character Analyzer
A guide to SymbolFYI's Character Analyzer — count characters, words, and bytes, inspect Unicode properties, and analyze text encoding character by character.
How to Use the SymbolFYI Unicode Lookup Tool
A guide to SymbolFYI's Unicode Lookup — enter a U+ codepoint to see the character's name, block, script, and full encoding details.
How to Use the SymbolFYI Symbol Search Tool
A complete guide to SymbolFYI's Symbol Search — find Unicode characters by name, keyword, HTML entity, or pasted character, with one-click copy in any format.
Font Fallback and Tofu: Why Characters Display as Empty Boxes
Understand font fallback — why characters render as empty boxes (tofu), how to build robust font stacks, unicode-range subsetting, and more.
Box Drawing Characters: Building Text-Based UI with Unicode
Use Unicode box drawing characters to build tables, borders, and text-based interfaces — the complete reference with copy-paste examples and CSS tips.
CJK Web Typography: Chinese, Japanese, and Korean Text on the Web
Master CJK web typography — font stacks, line breaking rules, ruby annotation, vertical writing, CSS text-spacing, and mixed-script layout techniques.
Whitespace Characters in Web Development: Beyond the Space Bar
Master all Unicode whitespace characters for web development — non-breaking space, thin space, em space, zero-width characters, and CSS white-space control.
Ligatures in Web Typography: From fi to Modern OpenType Features
Master web ligatures — standard ligatures (fi, fl), discretionary ligatures, CSS font-feature-settings, OpenType features, and accessibility implications.
Tofu: Why Characters Show as Empty Rectangles and How to Fix It
Understand tofu — the empty rectangle that appears when your font can't display a character. Learn causes, diagnosis, and font fallback solutions.
Unicode Accessibility Checklist: 15 Checks for Inclusive Text
A practical 15-point checklist for Unicode accessibility — from decorative symbol hiding to language declaration, RTL support, and proper text alternatives.
Accessible Emoji: How to Use Emoji Without Excluding Users
Make emoji accessible — screen reader behavior, aria-label patterns, avoiding emoji overuse, social media accessibility, and cognitive considerations.
WCAG and Special Characters: Meeting Accessibility Standards
How WCAG success criteria apply to Unicode symbols — text alternatives, contrast requirements, and specific techniques for special character accessibility.
ARIA and Unicode: Making Decorative Symbols Accessible
Use ARIA attributes to make Unicode symbols and emoji accessible — aria-label, aria-hidden, role=img patterns, and screen reader testing strategies.
How Screen Readers Handle Unicode Symbols and Emoji
Learn how screen readers announce Unicode symbols, emoji, and special characters — NVDA, JAWS, VoiceOver behavior differences and best practices.
Windows Alt Codes: Complete Reference for Special Characters
The complete Windows Alt code reference — how Alt codes work, the most useful codes for common symbols, and alternatives for modern Windows.
Unicode Hex Input on macOS: Type Any Character by Code Point
Enable and use the Unicode Hex Input keyboard on macOS — type any Unicode character by holding Option and typing its hex code point.
Dead Keys: How to Type Accented Characters Without a Special Keyboard
Master dead keys for typing accented characters — how they work on US International, UK Extended, and other keyboard layouts across all platforms.
Input Method Editors (IME): How CJK Text Input Works
Understand how Input Method Editors work — Japanese IME workflow, Chinese pinyin input, Korean hangul composition, and web form compatibility.
How to Type Special Characters on Linux: Compose Key and Unicode Input
Type special characters on Linux — Compose key sequences, Ctrl+Shift+U Unicode input, IBus/Fcitx input methods, and custom .XCompose files.
How to Type Special Characters on Windows: Alt Codes and Beyond
Type any special character on Windows — Alt codes, Win+. emoji panel, Character Map, Unicode hex input, and third-party tools like WinCompose.
How to Type Special Characters on Mac: The Complete Guide
Master typing special characters on macOS — Option key shortcuts, Character Viewer, Unicode Hex Input, dead keys, and emoji picker.
The Private Use Area: Custom Characters in Unicode
Explore Unicode's Private Use Areas — how they work, why icon fonts use them, PUA in corporate fonts, and the risks of PUA characters in data exchange.
Punycode and IDN: How Unicode Domain Names Work
How Internationalized Domain Names work — Punycode encoding, IDNA 2003 vs 2008, homograph attacks, and implementing IDN support in your applications.
Legacy Encodings: Latin-1, Windows-1252, Shift-JIS, and When You Still Need Them
A practical guide to legacy character encodings — when you'll encounter Latin-1, Windows-1252, Shift-JIS, EUC-KR, and how to convert them to UTF-8.
UTF-16 and Surrogate Pairs: Why JavaScript Strings Are Complicated
Understand UTF-16 encoding and surrogate pairs — why emoji have .length 2 in JavaScript, how to handle supplementary characters, and when UTF-16 matters.
Character Encoding Detection: How Browsers and Tools Guess Your Encoding
How encoding detection works — the algorithm browsers use, statistical detectors like chardet, BOM sniffing, and why detection is never 100% reliable.
Mojibake: Why Text Turns to Garbage and How to Fix It
Understand mojibake — garbled text from encoding mismatches. Learn to diagnose, fix, and prevent encoding errors in files, databases, and web applications.
UTF-8: The Complete Guide to the Web's Dominant Encoding
Everything about UTF-8 — how it works, why it won, byte patterns, BOM handling, validation, and common pitfalls for developers.
Unicode Collation: How to Sort Text Correctly Across Languages
Master Unicode collation — the Unicode Collation Algorithm, locale-aware sorting in JavaScript and Python, PostgreSQL ICU collations, and common pitfalls.
Character Encoding Detection: How to Identify Unknown Text Encoding
Detect character encodings in unknown text — BOM sniffing, statistical analysis with chardet, ICU detection, and why heuristics sometimes fail.
Web Fonts and Unicode Subsetting: Loading Only What You Need
Optimize web font loading with unicode-range subsetting — reduce font file sizes, improve load times, and handle multilingual content efficiently.
Soft Hyphen: Controlling Line Breaks in Web Typography
Master the soft hyphen (U+00AD) — how it controls word breaking in HTML, CSS hyphens property, browser behavior differences, and when to use ­ vs CSS.
IDN Homograph Attacks: When Unicode Becomes a Security Threat
Learn how attackers use Unicode lookalike characters to create phishing domains — how IDN homograph attacks work and how browsers defend against them.
Unicode in URLs: Percent-Encoding, Punycode, and IRIs
Understand how Unicode characters appear in URLs — percent-encoding for paths, Punycode for domains, IRIs, and Python/JavaScript encoding functions.
Python and Unicode: The Complete Developer's Guide
Master Unicode in Python — str vs bytes, unicodedata module, encoding/decoding, file I/O, normalization, and the Unicode sandwich pattern.
JavaScript and Unicode: Strings, Code Points, and Grapheme Clusters
Navigate JavaScript's UTF-16 string model — surrogate pairs, codePointAt, for...of iteration, Intl.Segmenter, and common Unicode pitfalls.
Diacritical Marks: Understanding Accents, Umlauts, and Combining Characters
A complete guide to diacritical marks in Unicode — precomposed vs combining characters, normalization, typing accented letters, and handling diacritics in code.
Unicode-Aware Regex: Property Escapes and Multilingual Patterns
Write regex patterns that work with Unicode — property escapes, script detection, emoji matching, and common pitfalls in JavaScript and Python.
CSS Content Property: Using Unicode Symbols in Stylesheets
Learn to use Unicode characters in CSS — the content property, escape sequences, custom list markers, decorative elements, and accessibility considerations.
HTML Entities: The Complete Guide to Character References
Master HTML entities — named references, numeric codes, hex notation, when escaping is required, and a reference table of the most useful entities.
Mathematical Symbols in Unicode: A Complete Reference
The definitive reference for mathematical symbols in Unicode — operators, Greek letters, set theory, logic, arrows, and where to find them by block.
Mathematical Notation in Unicode: From Clay Tablets to Code Points
How mathematical symbols were standardized in Unicode — the history of +, −, ×, ÷, =, π, ∑, ∫ and the challenges of encoding mathematical notation.
Braille in Unicode: How a Tactile System Became Digital Text
The story of Braille's journey into Unicode — from Louis Braille's 1824 invention to the 256-character Braille Patterns block in Unicode.
The History of Typography Marks: From Gutenberg to Unicode
How punctuation marks evolved from ancient Greece through Gutenberg's press to Unicode — the stories behind @, #, &, §, ¶, and more.
The History of Emoji: From Japanese Pagers to Universal Language
The complete history of emoji — from Shigetaka Kurita's 1999 designs for NTT DoCoMo to Unicode standardization and modern ZWJ sequences.
The History of Unicode: From Babel to a Universal Character Set
How the Unicode Consortium unified the world's writing systems — from the 1987 founding to Unicode 16.0 with over 154,000 characters.
The History of ASCII: How 128 Characters Shaped Computing
Trace ASCII's evolution from telegraph codes to the foundation of modern text — the 128 characters that defined computing's character set for decades.
Bullet (•) vs Middle Dot (·): Small Dots, Big Differences
Compare the bullet (•), middle dot (·), and other dot-like characters — proper usage in lists, navigation separators, and interpuncts.
Space Characters in Unicode: 20+ Invisible Characters Compared
Explore Unicode's space characters — regular space, non-breaking space, zero-width space, em space, thin space, and other invisible formatting characters.
Zero vs Letter O: Unicode Confusables and Homograph Attacks
How 0, O, and О (Cyrillic) create confusion — from font design to IDN homograph attacks, confusable detection, and security implications.
Minus vs Hyphen vs Dash: Five Characters That Look Like a Line
Navigate the confusing world of horizontal line characters — hyphen-minus, en dash, em dash, minus sign, and horizontal bar.
Variation Selectors: How Unicode Controls Text vs Emoji Display
Understand Unicode variation selectors — VS15 for text presentation, VS16 for emoji presentation, and how they control whether ☺ or 😊 appears.
Multiplication Sign (×) vs Letter X: Spot the Difference
Distinguish the multiplication sign (×, U+00D7) from lowercase x and uppercase X — visual comparison, Unicode properties, and proper usage in math.
Ellipsis (…) vs Three Dots (...): One Character or Three?
Compare the Unicode ellipsis character (…) with three period characters (...) — typographic differences, CSS text-overflow, and when each is appropriate.
Curly Quotes vs Straight Quotes: Typography's Most Common Mix-Up
Understand the difference between smart quotes (“ ”) and straight quotes (" ") — when to use each, code vs prose, and auto-conversion pitfalls.
En Dash vs Em Dash: When to Use – and —
Learn the difference between en dash (–) and em dash (—) — usage rules, typing methods, HTML entities, and CSS implementation.
Unicode CLDR: The Database Behind Every Localized App
Explore the Unicode Common Locale Data Repository — how CLDR powers number formatting, date patterns, collation, and pluralization worldwide.
Grapheme Clusters: Why String Length Is More Complicated Than You Think
Understand grapheme clusters — why 'café' can be 4 or 5 code points, why emoji have .length 2+ in JavaScript, and how to count what users actually see.
Unicode Version History: From 1.0 to 16.0 and Beyond
A complete history of Unicode versions — major milestones, character count growth, emoji additions, and the stability policy that keeps it all working.
CJK Unification: How Unicode Handles Chinese, Japanese, and Korean
Learn about Han Unification in Unicode — how shared CJK ideographs are unified, the controversy it creates, and how language tags affect rendering.
How Emoji Work in Unicode: From Code Points to Skin Tones
Discover how emoji are encoded in Unicode — ZWJ sequences, skin tone modifiers, variation selectors, and the emoji submission process.
Code Point vs Character vs Glyph: The Three Levels of Text
Understand the three levels of text representation — code points (numbers), characters (abstract identities), and glyphs (visual shapes in fonts).
Bidirectional Text in Unicode: How RTL and LTR Scripts Coexist
Understand Unicode's Bidirectional Algorithm — how Arabic, Hebrew, and other RTL scripts mix with LTR text in web pages and applications.
Unicode Properties and Categories: Classifying Every Character
Explore Unicode General Categories, Script property, and other character properties used in regex, text processing, and internationalization.
What Is a Code Point? Understanding Unicode's U+ Notation
Learn what Unicode code points are — the U+ notation system, how code points differ from characters and glyphs, and how to find any character's code point.
Unicode Normalization: NFC, NFD, NFKC, and NFKD Explained
Master Unicode normalization forms — when to use NFC vs NFD, canonical vs compatibility equivalence, and how normalization prevents bugs.
Unicode Encodings Explained: UTF-8, UTF-16, and UTF-32 Compared
Compare UTF-8, UTF-16, and UTF-32 encodings — how they work, when to use each, and why UTF-8 dominates the web.
Unicode Planes and Blocks: How 1.1 Million Code Points Are Organized
Understand Unicode's 17 planes and hundreds of blocks — from the Basic Multilingual Plane to supplementary planes for emoji and historic scripts.
What Is Unicode? The Universal Character Standard Explained
Learn what Unicode is, why it was created, and how it assigns a unique code point to every character in every writing system.