Compreso

A modern, responsive Unicode text compressor that reduces character count by replacing multi-character sequences with single Unicode characters (ligatures, fractions, symbols, and more).

Live Demo

Features

• Real-time compression — see results as you type
• 9 toggleable categories — choose which replacements to apply:
  1. Ligatures — Standard Unicode ligatures. Combines common letter pairs into single characters like 'ae' → 'æ', 'ffi' → 'ffi'.
  2. Compounds — Experimental combined characters that may have minor rendering defects in some fonts. Example: 'th' → 'ᵺ'.
  3. Fractions & Symbols — Replaces fractions, punctuation combos, and common symbols. Example: '1/2' → '½', '!!' → '‼'.
  4. Case Sensitivity — When enabled, only exact case matches are compressed. When disabled, tries both cases for uppercase entries.
  5. CJK Comp — CJK compatibility characters that visually resemble Latin letters (e.g., 'mg' → '㎎', 'ltd' → '㋏'). Enable Case Sensitivity for strict matching.
  6. Add Fix Chr — [EXPERIMENTAL] Prepends an invisible zero-width character that fixes CJK character rendering in some fonts. Shows a blue indicator when active.
  7. Emojify — Replaces emoji shortcodes with actual Unicode emoji characters. Example: ':cat:' → '🐱', ':fire:' → '🔥'.
  8. Words to Symbols — Replaces common words with their symbolic equivalents. Example: 'equals' → '=', 'percent' → '%'.
  9. Words to Numbers — [EXPERIMENTAL] Converts written-out numbers to digits. Example: 'one' → '1', 'twenty' → '20'.
• Progressive compression — Set a character limit and Compreso will apply replacements until the target length is reached
• Light/Dark theme — toggle or auto-detect system preference
• Copy button — one-click copy of compressed text
• Compression stats — progress bar + text showing % saved
• Responsive design — works on mobile and desktop

Usage

1. Open the live demo
2. Type or paste text in the input area
3. Watch the compressed output update in real-time
4. Toggle categories on/off to control which replacements apply
5. Set an optional character limit to enable progressive compression
6. Click "Copy" to copy the compressed text

How It Works

Ligatures

Standard Unicode ligatures combine two or more letters into a single character:

• ae → æ, AE → Æ, oe → œ, OE → Œ
• ff → ff, fi → fi, fl → fl, ffi → ffi, ffl → ffl
• ij → ij, IJ → IJ

Compounds

Experimental combined characters that may have minor rendering defects:

• th → ᵺ, st → st, uu → ﬓ

Fractions & Symbols

Fractions, punctuation combos, and symbols:

• 1/2 → ½, 1/3 → ⅓, 2/3 → ⅔, 3/4 → ¾
• !! → ‼, !? → ⁉, ?! → ⁈

CJK Compatibility Characters

These are Unicode characters from the CJK Compatibility block that visually resemble Latin letters:

• mg → ㎎ (milligram), kg → ㎏ (kilogram), km → ㎡ (kilometer)
• cm → ㎝, mm → ㎟, ltd → ㋏ (limited company)
• wc → ㍿ (water closet), ha → ㏊ (hectare)

Words to Symbols

Common word replacements:

• equals → =, plus → +, minus → -, times → ×
• divided by → ÷, percent → %, dollar → $

Words to Numbers

Converts written-out numbers to digits:

• one → 1, two → 2, twenty → 20
• hundred → 100, thousand → 1000

Case Sensitivity

When disabled (default), Compreso adds both uppercase and lowercase variants for matching:

• If ltd is in the dictionary and Case Sensitivity is OFF, LTD will also match
• If LTD is in the dictionary and Case Sensitivity is OFF, ltd will also match

When enabled, only exact case matches are compressed.

Add Fix Chr (Experimental)

Prepends a zero-width non-joiner character (U+200C) to the text. This can fix CJK character rendering issues in some fonts that don't properly handle CJK compatibility characters. When active, a blue indicator appears on the output box.

Progressive Compression

When a character limit is set, Compreso applies replacements in priority order until the text fits within the limit:

1. Space compression (5 spaces → em space, etc.)
2. Ligatures
3. Fractions & Symbols
4. Compounds
5. CJK Comp
6. Emojify
7. Words to Symbols
8. Words to Numbers
9. Add Fix Chr (if any replacements were applied)

Tech Stack

• Pure HTML5, CSS3, JavaScript (no framework, no build step)
• Noto Sans webfont for Unicode rendering
• GitHub Pages hosting

License

MIT