In the world of professional subtitling, choosing the right subtitle file format is crucial.
Whether you're producing content for a global streaming platform, a regional TV broadcaster, or cinematic release, the file type you deliver can directly impact timing, formatting, and compatibility.
Below is an overview of the most commonly used subtitle file formats, their differences, and where they best apply.
Use Case: Universal / Streaming platforms / YouTube / Archiving
Pros:
Widely supported (Netflix, Amazon Prime, YouTube)
Simple text-based format
Lightweight and easy to edit
Cons:
No support for rich formatting (font, color, style)
No metadata or positioning control
Best For: Online streaming platforms and quick subtitle exchanges.
Use Case: Broadcast television (Europe)
Pros:
Standard format for European TV broadcasters (EBU)
Includes positioning, font style, in/out times
Cons:
Requires specialized software
Less intuitive for non-professionals
Best For: Traditional TV broadcasting, especially in Europe.
Use Case: Professional broadcast / Cinema / Mastering
Pros:
Supports precise timing and positioning
Includes metadata, formatting, and language codes
Used by professional subtitling houses
Cons:
Requires proprietary software
Not compatible with open platforms like YouTube
Best For: High-end post-production, film distribution, and TV mastering.
TTML (Timed Text Markup Language) – Used by Netflix, XML-based with rich formatting.
DFXP (Distribution Format Exchange Profile) – A subset of TTML, often used in streaming.
VTT (WebVTT) – HTML5 compatible, used for web players.
ASS/SSA (Advanced SubStation Alpha) – Supports rich formatting, ideal for anime/fansubs.
Universal Use: SRT
Broadcast Standard (EU): STL
Professional Mastering: PAC
Netflix: TTML / DFXP
Amazon Prime: SRT / TTML
YouTube: SRT / VTT
1. What is the most universal format?
SRT is the most compatible and widely accepted due to its simplicity and flexibility.
2. Why does Netflix prefer TTML?
TTML supports rich styling and precise timing, important for high production quality.
3. When is STL used?
STL is the standard for TV broadcast, especially in Europe.
4. Which format is best for DVD and Blu-ray?
PAC is most commonly used in film post-production and physical releases.
5. How to choose the right format?
Always check the client or platform requirements. For most online platforms, SRT is a safe and practical choice.
When deciding on a subtitle format, consider the final platform, required features (styling, positioning, metadata), and technical compatibility.
At Sublandia, we deliver subtitles in all major formats and tailor them for specific use cases—whether you're uploading to Netflix, preparing content for TV, or mastering a feature film.
Contact Sublandia for expert subtitling solutions tailored to your distribution channel.
SRT (SubRip Subtitle File) is the simplest and most widely used subtitle format. It consists of numbered sections containing time codes and subtitle text.
Each section starts with a sequence number.
Then come the time codes (start and end time) in hours:minutes:seconds,milliseconds format.
The subtitle text is below.
There is a blank line between sections.
Subtitle Edit — free subtitle creation and editing tool.
Notepad or any plain text editor (if you know the structure).
Use short, clear lines (max 2 lines per segment).
Synchronize subtitles precisely with speech.
Avoid overlapping subtitles.
Check spelling and style.
TTML (Timed Text Markup Language) is an XML-based subtitle format that supports rich styling and precise display control.
begin and end attributes set the display time.
Subtitle text is inside <p> tags.
Styling (colors, fonts, positioning) can be added with extra attributes and styles.
Subtitle Edit (can export TTML).
EZTitles (professional software).
Professional production software.
Flexibility and device compatibility.
Standard for streaming services (Netflix, Amazon).
Supports fonts, colors, positioning, and complex animations.
Check source video:
Ensure accurate video timestamps.
Synchronization:
Subtitles must be tightly synced with speech or audio.
Formatting:
Keep subtitles clear, concise, and compliant with target platform standards.
File encoding:
Use UTF-8 encoding to support special characters (e.g., accented letters).
Testing:
Always test subtitles on the target platform/device before final delivery.