OTF vs SVG: Complete Format Comparison
Comprehensive comparison of OpenType Font (OTF) and SVG Font formats covering technical differences, performance, browser support, and why SVG fonts are obsolete
In Simple Terms
SVG fonts are completely obsolete with 0% browser support (last browser removed support 2018). OTF is the modern universal standard.SVG fonts were 289% larger than WOFF (350 KB vs 90 KB) with terrible performance. Never use SVG fonts—they're deprecated.Use OTF for desktop. Convert OTF to WOFF2 for web (68% smaller). Remove all SVG font references immediately.
In this article
OpenType Font (OTF) and SVG Font formats represent fundamentally different approaches to digital typography, with OTF being a professional binary font format and SVG fonts being an experimental XML-based specification that ultimately failed. OTF, jointly developed by Adobe and Microsoft in 1996, stores font data as optimized binary tables with either TrueType (quadratic Bézier) or PostScript (cubic Bézier) outlines, designed for efficient desktop use with advanced typographic features. SVG fonts, introduced in the SVG 1.1 specification (2001), define glyphs as XML-encoded vector paths within Scalable Vector Graphics documents, intended to enable font embedding directly in SVG markup without requiring separate font files.
The critical distinction is that OTF remains the desktop standard and source format for web fonts, while SVG fonts are completely obsolete with zero browser support as of 2025. OTF files (150-300 KB) use compact binary encoding optimized for parsing speed and file size. SVG fonts (200-400 KB) use verbose XML text representation, making them 30-100% larger than equivalent OTF files while offering no technical advantages. Chrome removed SVG font support in 2013, Firefox never fully implemented it, and Safari iOS (the last holdout) deprecated them in 2018. The W3C officially deprecated SVG fonts in favor of WOFF, which wraps OTF/TrueType data with compression for superior web performance.
This comprehensive guide compares OTF and SVG fonts to clarify why SVG fonts failed and should be removed from any legacy code. You'll learn the technical specifications of both formats, how XML overhead makes SVG fonts inefficient, browser compatibility showing SVG fonts' complete rejection by the industry, performance comparisons demonstrating SVG fonts' poor file sizes and rendering speed, historical context of why SVG fonts were created and abandoned, and modern recommendations to use OTF as source and convert to WOFF2 for web delivery. Whether maintaining legacy projects or understanding web font history, this guide provides essential knowledge about these formats' contrasting fates.
Format Overview
OpenType Font (OTF)
History and Purpose:
- • Developed by Adobe and Microsoft (1996)
- • Unified TrueType and PostScript Type 1 formats
- • Designed for professional desktop typography
- • Industry standard for 30+ years
- • Actively maintained and evolved (2025)
Technical Characteristics:
- • Binary table-based structure
- • TrueType (quadratic) or PostScript/CFF (cubic) outlines
- • Comprehensive OpenType features (ligatures, kerning, alternates)
- • Efficient binary encoding
- • Extensions: .otf (PostScript) or .ttf (TrueType)
Current Status (2025):
- • Desktop standard worldwide
- • Source format for WOFF/WOFF2 conversion
- • File size: 150-300 KB (Latin fonts)
- • Platform: Windows, macOS, Linux, mobile
SVG Font Format
History and Purpose:
- • Introduced in SVG 1.1 specification (2001)
- • Designed to embed fonts within SVG documents
- • Experimental approach using XML/text encoding
- • Never gained widespread adoption
- • Deprecated and removed from browsers
Technical Characteristics:
- • XML-based text format
- • Glyphs defined as SVG path elements
- • Embedded in <defs> and <font> tags
- • No hinting support (relies on anti-aliasing)
- • Limited OpenType feature support
Current Status (2025):
- • Zero browser support
- • Chrome removed 2013, Safari iOS removed 2018
- • W3C deprecated in favor of WOFF
- • DO NOT use in any projects
Why SVG Fonts Failed Completely
SVG fonts were rejected by the industry for fundamental reasons:
- Larger file sizes: XML text is 30-100% larger than binary OTF
- Slower parsing: XML parsing + SVG rendering is slower than native font rendering
- No hinting: Poor rendering quality at small sizes
- Limited features: Couldn't support advanced OpenType features
- Browser rejection: Chrome/Firefox refused to implement due to inefficiency
- Better alternative: WOFF emerged with compression and universal support
Technical Differences
Comprehensive Technical Comparison
| Feature | OTF | SVG |
|---|---|---|
| Data Format | Binary (optimized) | XML/Text (verbose) |
| Glyph Definition | Binary curve data | SVG path strings |
| File Size | 168 KB (baseline) | 350 KB (108% larger) |
| Hinting | Full TrueType/PostScript | None |
| OpenType Features | Full support | Limited/none |
| Parsing Speed | Fast (binary) | Slow (XML) |
| Rendering | OS-level font engine | SVG rendering engine |
| Browser Support | All browsers | None (removed) |
| Desktop Install | Yes (native) | No |
| Status | Active standard | Obsolete |
Binary vs XML Encoding
OTF Binary Encoding:
- • Glyph data stored as compact binary coordinates
- • Efficient representation: ~50-200 bytes per glyph
- • Fast parsing by operating system
- • Direct memory mapping possible
- • Example: Letter "A" = ~100 bytes binary
SVG XML Encoding:
- • Glyph data stored as XML text with path commands
- • Verbose representation: ~200-500 bytes per glyph
- • Slow XML parsing required
- • Additional SVG rendering overhead
- • Example: Letter "A" = ~300 bytes XML text
Result: OTF is 2-3× more efficient in both file size and parsing speed.
SVG Font Structure Example
Historical reference showing verbose XML structure:
<svg xmlns="http://www.w3.org/2000/svg">
<defs>
<font id="MyFont" horiz-adv-x="1000">
<font-face font-family="MyFont" units-per-em="1000"/>
<missing-glyph horiz-adv-x="500"/>
<glyph unicode="A" horiz-adv-x="722"
d="M361 0L361 250L111 250L111 0L54 0L54 674L168 674... (long path)"/>
<!-- Repeated for every character -->
<!-- Results in 200-400 KB file vs 150-300 KB OTF -->
</font>
</defs>
</svg>Technical Problems with SVG Fonts
- XML overhead: Tags, attributes, namespaces add 50-100% size bloat
- Path verbosity: Text path commands vs compact binary coordinates
- No hinting: Cannot encode pixel-grid alignment instructions
- Limited features: Can't represent complex OpenType GSUB/GPOS tables
- Rendering overhead: SVG engine is slower than native font rendering
- Memory inefficient: DOM nodes consume more memory than font tables
Browser Compatibility
Browser Support Timeline
| Browser | OTF | SVG | SVG Status |
|---|---|---|---|
| Chrome | ✓ | ✗ | Removed v38 (2013) |
| Firefox | ✓ | ✗ | Never implemented |
| Safari (Desktop) | ✓ | ✗ | Deprecated 2018 |
| Safari (iOS) | ✓ | ✗ | Removed iOS 11.3 (2018) |
| Edge | ✓ | ✗ | Never supported |
Current Status (2025): SVG fonts have 0% browser support. OTF works universally.
SVG Font Deprecation Timeline
- 2001: SVG 1.1 introduces SVG fonts as experimental feature
- 2008-2012: Safari iOS supports SVG fonts (before WOFF support)
- 2012: WOFF emerges as superior alternative
- 2013: Chrome removes SVG font support (never widely used)
- 2016: W3C officially deprecates SVG fonts in favor of WOFF
- 2018: Safari iOS 11.3 removes SVG font support completely
- 2025: Zero browser support, format completely obsolete
Legacy @font-face with SVG
Historical example showing outdated SVG font usage (DO NOT USE):
/* OUTDATED - DO NOT USE THIS CODE */
@font-face {
font-family: 'MyFont';
src: url('font.woff2') format('woff2'),
url('font.woff') format('woff'),
url('font.ttf') format('truetype'),
url('font.svg#MyFont') format('svg'); /* REMOVE THIS */
}
/* MODERN APPROACH (2025) - USE THIS */
@font-face {
font-family: 'MyFont';
src: url('font.woff2') format('woff2'),
url('font.woff') format('woff');
font-display: swap;
}
/* SVG font line removed - obsolete format */Performance Comparison
File Size Comparison
Example: Open Sans Regular with full Latin character set
| Format | File Size | vs OTF | Status |
|---|---|---|---|
| OTF | 168 KB | Baseline | Active |
| SVG | 350 KB | 108% larger | Obsolete |
| SVG (gzipped) | 210 KB | 25% larger | Still obsolete |
| WOFF | 90 KB | 46% smaller | Active |
| WOFF2 | 53 KB | 68% smaller | Best |
Key finding: SVG is the worst format. Even gzipped, it's 25% larger than uncompressed OTF and 296% larger than WOFF2.
Why SVG Fonts Perform Poorly
- XML overhead: Tags, attributes, namespaces add massive bloat
- Text encoding: Path commands as text strings vs binary
- Parsing cost: XML parsing is inherently slower than binary
- Rendering overhead: SVG rendering engine is slower than native fonts
- No optimization: Can't use font-specific compression like WOFF2
- Memory consumption: DOM nodes for glyphs use more memory
WOFF2 Advantages Over Both OTF and SVG
- • vs OTF: 68% smaller (53 KB vs 168 KB) via Brotli compression
- • vs SVG: 85% smaller (53 KB vs 350 KB), much faster rendering
- • Universal support: 97%+ browsers vs 0% for SVG fonts
- • Full features: All OpenType features preserved
- • Native rendering: OS font engine, not SVG renderer
- • W3C standard: Actively maintained, industry-backed
Historical Context
Why SVG Fonts Were Created
SVG fonts emerged from a specific historical need:
- Problem: Early 2000s, no web font standard existed
- SVG context: SVG documents wanted embedded fonts for portability
- Conceptual appeal: Fonts are vector graphics, SVG is vector graphics
- Implementation: Define glyphs as SVG paths within document
- Reality: Conceptually interesting but technically flawed
Why Safari iOS Temporarily Used SVG Fonts
Safari iOS (2008-2012) was the only major browser to support SVG fonts:
- • iPhone's early iOS lacked WOFF support
- • Designers wanted custom fonts on mobile web
- • SVG fonts were only option before WOFF arrived
- • Apple deprecated them once WOFF became available
Lesson: SVG fonts were always a stopgap, never the intended solution.
Modern Recommendations
Use OTF For:
- • Desktop installation: Windows, macOS, Linux
- • Design applications: Photoshop, Illustrator, InDesign
- • Source files: Master format for font management
- • Conversion source: Convert OTF to WOFF2 for web
Never Use SVG Fonts:
- • Zero browser support: Removed from all browsers
- • Worst performance: Largest files, slowest rendering
- • No advantages: Inferior to all alternatives
- • Action: Remove from all projects immediately
Modern Workflow (2025)
- Start with OTF/TTF source files
- Install OTF on desktop for design work
- Convert OTF to WOFF2 for web delivery
- Optionally create WOFF for very old browser fallback
- Implement with @font-face (WOFF2 + WOFF only)
@font-face {
font-family: 'MyFont';
src: url('/fonts/font.woff2') format('woff2'),
url('/fonts/font.woff') format('woff');
font-display: swap;
}
/* No OTF: Not optimized for web */
/* No SVG: Obsolete, removed from browsers */Removing SVG Fonts Checklist
- ☐ Search codebase for .svg font references
- ☐ Remove url('font.svg#FontName') from @font-face
- ☐ Remove format('svg') declarations
- ☐ Delete .svg font files from server
- ☐ Ensure WOFF2 and WOFF versions exist
- ☐ Test in modern browsers (Chrome, Safari, Firefox)
- ☐ Verify fonts load correctly
- ☐ Remove any SVG font polyfills or fallback scripts
Summary: OTF vs SVG
OTF and SVG fonts represent contrasting approaches: OTF as efficient binary format that became the desktop standard, SVG as experimental XML-based format that completely failed. SVG fonts are 108% larger than OTF (350 KB vs 168 KB) due to XML overhead, with slower parsing and no technical advantages. Chrome removed support in 2013, Firefox never implemented it, and Safari iOS removed it in 2018. Browser support is 0% as of 2025.
Use OTF for desktop installation and as source files for web conversion. Never use SVG fonts—they are obsolete with zero browser support and inferior performance. Convert OTF to WOFF2 (53 KB, 97%+ support) for optimal web delivery. WOFF2 is 85% smaller than SVG fonts (53 KB vs 350 KB) while providing superior features and universal compatibility. Remove SVG font references from all projects immediately. OTF thrives; SVG fonts are a cautionary tale in web standards.
Written & Verified by
Sarah Mitchell
Product Designer, Font Specialist
OTF vs SVG FAQs
Common questions answered about this font format comparison