Introduction
If you're involved in video streaming, you've likely encountered two main acronyms: HLS (HTTP Live Streaming) and MPEG-DASH (Dynamic Adaptive Streaming over HTTP). Both are adaptive bitrate streaming protocols that dominate the modern web, but they have distinct histories, features, and use cases.
In this guide, we'll compare them head-to-head to help you understand which one is right for your needs in 2025.
What is HLS?
HLS (HTTP Live Streaming) was developed by Apple in 2009. It was originally designed to solve streaming issues on iPhones but has since become the most widely supported streaming protocol globally.
- File Extension: .m3u8 (playlist), .ts (video segments)
- Video Codecs: H.264, H.265 (HEVC)
- Audio Codecs: AAC, MP3, AC-3
What is MPEG-DASH?
MPEG-DASH is an open standard developed by the Moving Picture Experts Group (MPEG). Unlike HLS, which is proprietary to Apple (though widely adopted), DASH is codec-agnostic and vendor-independent.
- File Extension: .mpd (Media Presentation Description)
- Video Codecs: Any (H.264, H.265, VP9, AV1)
- Audio Codecs: Any (AAC, Opus, etc.)
Key Differences
| Feature | HLS | MPEG-DASH |
|---|---|---|
| Developer | Apple | MPEG (International Standard) |
| Codec Support | Limited (H.264/H.265) | Agnostic (Supports VP9, AV1) |
| Container Format | MPEG-2 TS (legacy), fMP4 | fMP4, WebM |
| DRM | FairPlay (Apple) | Widevine (Google), PlayReady (Microsoft) |
| Latency | Higher (typically 6-30s) | Lower (can be <5s) |
Pros & Cons
HLS Pros & Cons
✅ Pros
- Native support on all Apple devices
- Widely supported on almost all players
- Simple infrastructure requirements
❌ Cons
- Higher latency by default
- Restricted codec support (mostly)
DASH Pros & Cons
✅ Pros
- Codec agnostic (supports open codecs like AV1)
- Lower latency options
- International standard
❌ Cons
- No native support on iOS/Safari
- More complex to configure
Device Compatibility
This is often the deciding factor.
- iOS / Safari: Only supports HLS natively. DASH requires third-party apps.
- Android / Chrome: Supports both (DASH via MSE/EME).
- Desktop Browsers: Most support both via JavaScript libraries (like Video.js, hls.js, dash.js).
Critical Note: If your audience uses iPhones, you MUST have an HLS stream. iOS Safari does not support DASH.
The Verdict: Which to Choose?
So, which one wins?
Choose HLS if:
- You want maximum compatibility (especially with Apple devices).
- You want a simpler setup.
- You are streaming to a general audience.
Choose DASH if:
- You need to use open-source codecs like VP9 or AV1 to save bandwidth.
- You require advanced DRM features (Widevine/PlayReady) for premium content.
- You have a specific need for low-latency streaming on supported devices.
The Hybrid Approach: Many premium streaming services (like Netflix and YouTube) use both. They serve HLS to Apple devices and DASH to everything else. However, for most smaller projects, HLS is the safer, one-size-fits-all choice.