TTF vs DFONT: Complete Format Comparison
Comprehensive comparison of TrueType Font (TTF) and Data Fork Font (DFONT) formats covering technical differences, platform compatibility, and conversion methods
In Simple Terms
DFONT is macOS-only legacy container format. Same TrueType data as TTF, just different packaging. Only works on Mac.Convert DFONT to TTF for cross-platform compatibility. TTF works on Windows, macOS, Linux, and web. DFONT only works on macOS.For web: Convert DFONT to TTF first, then TTF to WOFF2. Use TTF for desktop cross-platform work, WOFF2 for modern websites.
In this article
TrueType Font (TTF) and Data Fork Font (DFONT) represent two different packaging methods for the same underlying TrueType font technology, distinguished primarily by their storage structure rather than font data differences. TTF is the universal standard format storing font data in a single file with a specific binary structure compatible across Windows, macOS, and Linux. DFONT is a macOS-specific container format that stores TrueType font data in the data fork of a file (rather than the resource fork), created during Apple's transition to OS X to maintain compatibility while moving away from legacy resource fork architecture.
The fundamental distinction lies in file structure, not font content. A TTF file contains identical TrueType glyph data, hinting instructions, and metrics as a DFONT file—the difference is purely in how this data is packaged. TTF uses a standard table-based structure with well-defined headers and offsets. DFONT wraps the same TrueType data within a macOS data fork structure, adding a 'dfont' resource type identifier. Both formats contain identical glyph outlines, kerning information, and OpenType features, making them functionally equivalent once properly extracted or converted.
This comprehensive guide compares TTF and DFONT across all relevant dimensions to clarify their relationship and practical differences. You'll learn the historical context of why DFONT was created during macOS evolution, detailed technical differences in file structure and packaging, platform compatibility showing DFONT's macOS-only limitation, conversion methods for extracting TTF data from DFONT containers, appropriate use cases for each format in modern development, and migration strategies for converting legacy DFONT files to universal TTF format. Whether working with macOS font libraries or planning cross-platform projects, this guide provides essential knowledge for handling both formats effectively.
Format Overview
TrueType Font (TTF)
History and Purpose:
- • Developed by Apple in 1989, licensed to Microsoft in 1991
- • Designed as cross-platform font format for desktop systems
- • Became industry standard supported by all operating systems
- • Uses standard file structure independent of OS-specific features
- • Remains the universal format for desktop fonts today
Technical Characteristics:
- • Binary format with table-based structure
- • Self-contained with all font data in single file
- • Platform-independent file structure
- • Direct access to font tables via offset directory
- • Supports all TrueType features: hinting, kerning, OpenType
File Characteristics:
- • Extension: .ttf
- • Typical size: 150-300 KB (Latin fonts)
- • Platform support: Universal (Windows, macOS, Linux)
- • Status: Current standard for desktop and web
Data Fork Font (DFONT)
History and Purpose:
- • Created by Apple for Mac OS X (2001) during resource fork transition
- • Designed to store TrueType data in data fork instead of resource fork
- • Enabled font portability to non-HFS+ filesystems (FAT32, NTFS)
- • Used primarily for system fonts in early OS X versions
- • Gradually replaced by standard TTF/OTF files in modern macOS
Technical Characteristics:
- • macOS-specific container format
- • Contains standard TrueType font data wrapped in data fork
- • Uses 'dfont' resource type identifier
- • Identical glyph data to TTF, different packaging
- • Requires macOS or specialized tools to read
File Characteristics:
- • Extension: .dfont
- • Typical size: Similar to TTF (150-300 KB)
- • Platform support: macOS only (limited)
- • Status: Legacy format, use TTF for new projects
Key Understanding: Same Font Data, Different Packaging
Critical concept: TTF and DFONT contain identical TrueType font data. The difference is only in how the data is stored:
- • Same glyphs: Identical curve definitions, same visual appearance
- • Same hinting: Identical TrueType hinting instructions
- • Same metrics: Identical advance widths, kerning, line spacing
- • Same features: Identical OpenType features if present
- • Only difference: File structure (how data is organized on disk)
Converting DFONT to TTF extracts the TrueType data and rewrites it in standard TTF structure with zero quality loss.
Technical Differences
Detailed Technical Comparison
| Aspect | TTF | DFONT |
|---|---|---|
| Font Data | TrueType tables | Same TrueType tables |
| File Structure | Standard TrueType format | macOS data fork container |
| Header | Standard sfnt header | 'dfont' resource header |
| Glyph Outlines | Quadratic Bézier | Identical Bézier |
| Hinting | TrueType instructions | Same instructions |
| File Size | 150-300 KB | ~Same (minimal overhead) |
| Cross-Platform | Yes (universal) | No (macOS only) |
| Conversion | Standard format | Requires extraction |
| Recommendation | Use for all projects | Legacy only |
File Structure Breakdown
TTF Structure:
- • Offset table: Points to all font tables
- • Table directory: Lists all tables with checksums
- • Font tables: Standard TrueType tables (glyf, loca, head, etc.)
- • Direct access: Any program can read tables immediately
DFONT Structure:
- • Data fork header: macOS-specific 'dfont' type identifier
- • Resource map: Maps to font resources within file
- • Font resources: Contains same TrueType tables as TTF
- • Indirect access: Requires macOS APIs or extraction tools
Why DFONT Was Created
Historical context for understanding DFONT's purpose:
- Classic Mac OS (pre-2001): Stored fonts in resource forks, causing problems on non-HFS filesystems
- OS X transition: Moved to Unix-based system, needed compatibility with non-HFS filesystems
- DFONT solution: Store font data in data fork (visible on all filesystems) while maintaining Mac compatibility
- Temporary bridge: Allowed migration from resource forks without breaking existing systems
- Modern macOS: Now prefers standard TTF/OTF files like other platforms
Multiple Fonts in DFONT
One unique feature of DFONT: A single .dfont file can contain multiple font faces (Regular, Bold, Italic, Bold Italic) as separate resources, similar to TrueType Collections (.ttc).
Example:
- • Helvetica.dfont might contain: Regular, Bold, Italic, Bold Italic
- • Extraction creates separate TTF files: Helvetica-Regular.ttf, Helvetica-Bold.ttf, etc.
- • This collection feature is why some DFONT files are larger (600-1200 KB)
Platform Compatibility
Platform Support Matrix
| Platform/Software | TTF | DFONT | Notes |
|---|---|---|---|
| Windows | ✓ | ✗ | No DFONT support |
| macOS | ✓ | ✓ | Both supported |
| Linux | ✓ | ✗ | No DFONT support |
| iOS/iPadOS | ✓ | ✗ | TTF/OTF only |
| Web Browsers | ✓ | ✗ | No DFONT support |
| Adobe CC | ✓ | ~ | Limited on Mac only |
| Office 365 | ✓ | ~ | Mac only, unreliable |
Key finding: DFONT only works reliably on macOS. TTF works everywhere.
DFONT Limitations
- No Windows support: Windows cannot read DFONT files at all
- No Linux support: Standard Linux font systems don't recognize DFONT
- No web use: Browsers cannot use DFONT files (must be TTF/WOFF/WOFF2)
- Application issues: Even on macOS, some apps don't handle DFONT well
- File sharing problems: Sending DFONT to non-Mac users makes fonts unusable
- Modern macOS preference: macOS now prefers standard TTF/OTF files
TTF Universal Compatibility
TTF works everywhere without conversion or special handling:
- • Desktop: Windows, macOS, Linux all support TTF natively
- • Mobile: iOS, Android use TTF/OTF for app fonts
- • Web: TTF works in browsers (though WOFF2 preferred)
- • Applications: All design/office software supports TTF
- • File sharing: TTF files work for all recipients
- • Future-proof: TTF is the standard, won't become obsolete
Conversion and Extraction
Method 1: Using FontForge (Free, Cross-Platform)
Installation:
# macOS brew install fontforge # Windows # Download from fontforge.org # Linux sudo apt-get install fontforge
Conversion Process:
- Open FontForge application
- File → Open → Select .dfont file
- If multiple fonts, FontForge shows list (select one)
- File → Generate Fonts
- Select "TrueType" format
- Click Generate → Save as .ttf file
Method 2: Using Online Converter
Steps:
- Visit font-converters.com or similar converter site
- Upload .dfont file
- Select "TTF" as output format
- Click Convert
- Download resulting .ttf file(s)
Note: If DFONT contains multiple fonts, you may get multiple TTF files (one per face).
Method 3: Command-Line with Python
Using FontTools:
# Install FontTools
pip install fonttools
# Extract TTF from DFONT
# Note: If multiple fonts in DFONT, extracts all
python -c "from fontTools.ttLib import TTFont; \
font = TTFont('Helvetica.dfont'); \
font.save('Helvetica.ttf')"Conversion Notes
- • Zero quality loss: Conversion extracts identical TrueType data
- • No re-rendering: Glyphs are not redrawn, just repackaged
- • Multiple fonts: One DFONT may yield multiple TTF files
- • File size: TTF files are similar size to original DFONT
- • Naming: Some tools auto-generate TTF names from DFONT metadata
- • Licensing: Ensure you have rights to convert/use the font
Use Cases and Recommendations
When to Use TTF
Always Use TTF For:
- • Cross-platform projects: Ensures compatibility everywhere
- • File sharing: Recipients on any OS can use TTF
- • Web projects: Convert TTF to WOFF2 for web use
- • Mobile apps: iOS/Android use TTF/OTF formats
- • Design deliverables: Clients can use on Windows/Mac/Linux
- • Font development: TTF is universal source format
Recommendation: Use TTF as your primary font format for all projects.
When DFONT Might Appear
You might encounter DFONT in:
- • macOS system fonts: /System/Library/Fonts/ (legacy)
- • Old Mac software: Apps from early OS X era
- • Font archives: Old Mac font collections
- • Legacy projects: Websites/designs from 2000s Mac era
Action: Convert DFONT to TTF for compatibility and future-proofing.
Don't Use DFONT For New Projects
- • Limited compatibility: Only works reliably on macOS
- • Legacy format: Even Apple moved to TTF/OTF
- • No web support: Cannot use in websites
- • Sharing issues: Non-Mac users cannot use DFONT
- • Unnecessary complexity: TTF does everything DFONT does, universally
Migration to Modern Formats
Complete Migration Workflow
- Identify DFONT files: Search project for .dfont extensions
- Check licensing: Verify you have rights to convert/use fonts
- Convert to TTF: Use FontForge, online converter, or FontTools
- Organize: Place TTF files in /fonts/ directory with clear naming
- Update references: Change file paths from .dfont to .ttf
- Test thoroughly: Verify fonts work on Windows, Mac, Linux
- Web conversion: If for web, convert TTF to WOFF2
- Archive originals: Keep DFONT files as backup, don't delete immediately
For Web Projects
Complete workflow from DFONT to web-ready fonts:
- Convert DFONT → TTF (using methods above)
- Convert TTF → WOFF2 (using FontTools or online converter)
- Optionally create WOFF fallback
- Implement with proper @font-face CSS
- Test in modern browsers
@font-face {
font-family: 'MyFont';
src: url('/fonts/font.woff2') format('woff2'),
url('/fonts/font.woff') format('woff');
font-display: swap;
}Migration Checklist
- ☐ Located all DFONT files in project
- ☐ Verified font licenses allow conversion
- ☐ Converted DFONT to TTF (zero quality loss)
- ☐ For web: Converted TTF to WOFF2
- ☐ Updated all file references in code
- ☐ Tested fonts on Windows, macOS, Linux
- ☐ Verified correct font weights/styles load
- ☐ Archived original DFONT files
- ☐ Documented font sources and licenses
Summary: TTF vs DFONT
TTF and DFONT contain identical TrueType font data—the only difference is file packaging. TTF uses universal format readable on all platforms. DFONT is a macOS-specific container created during OS X transition from resource forks, working only on Mac systems. Both have same glyphs, hinting, metrics, and features. Converting DFONT to TTF extracts identical data with zero quality loss.
Always use TTF for new projects—it works everywhere (Windows, macOS, Linux, web, mobile). DFONT is a legacy format even Apple has moved away from in modern macOS. If you encounter DFONT files, convert them to TTF using FontForge or online converters for universal compatibility. For web use, convert TTF to WOFF2. TTF is the universal standard; DFONT is historical curiosity from Mac transition era.
Written & Verified by
Sarah Mitchell
Product Designer, Font Specialist
TTF vs DFONT FAQs
Common questions answered about this font format comparison