| Format | Best for | Styling? | Frame-accurate? | Apple-friendly? |
|---|---|---|---|---|
| SRT | Universal interchange | No | No | Yes (import only) |
| VTT | Web players | CSS-based | No | No |
| FCPXML | Final Cut Pro projects | Yes (full) | Yes | Yes (native) |
| iTT | Apple ecosystem delivery | Yes | Yes | Yes (native) |
| TTML / DFXP | Broadcast captions | Yes | Yes | No |
| SCC | US broadcast (CEA-608) | Limited | Yes | No |
SRT is the workhorse of subtitle formats. It's a plain text file with timecodes and text โ nothing more. Every operating system, every player, every video platform accepts it.
1
00:00:01,000 --> 00:00:03,500
Welcome to JianHeBox
2
00:00:04,000 --> 00:00:06,500
Free subtitle converter
Strengths: Universal, simple, human-readable, easy to edit in any text editor.
Limitations: No styling (font, color, position), no metadata, milliseconds- level precision (not frame-accurate).
Use SRT when: You're posting to YouTube, Vimeo, LinkedIn, or any other general-purpose platform. You're sharing subtitles with a translator. You want a file you can read and edit by hand.
VTT is the web-native subtitle format. Browsers play it directly in
WEBVTT
00:00:01.000 --> 00:00:03.500
Welcome to JianHeBox
00:00:04.000 --> 00:00:06.500
Free subtitle converter
Strengths: Browser-native, CSS styling, voice tags for speaker labels, region positioning.
Limitations: Doesn't work in most NLEs (FCP, Premiere, Resolve), less universally supported than SRT.
Use VTT when: You're building a web player. You're delivering HTML5 video. You need CSS-style positioning.
FCPXML is Apple's full project interchange format. It's an XML representation of a Final Cut Pro project โ including sequences, clips, titles, and effects. FCPXML 1.14 (current) supports titles with custom position parameters, motion templates, and effects.
<param name="ไฝ็ฝฎ" key="9999/10393/10394/1/100/101" value="0 378"/>
<text>
<text-style ref="ts1">Welcome to JianHeBox</text-style>
</text>
Strengths: Frame-accurate, full styling control, integrates with FCP's Motion templates, includes position parameters.
Limitations: Final Cut Pro only (Premiere and Resolve can't import FCPXML), complex schema, brittle (wrong uid or missing param fails the import).
Use FCPXML when: You're working entirely in Final Cut Pro and you need precise control over caption styling and position. You're building a complex project where captions integrate with other titles.
iTT is Apple's delivery format, an XML dialect of W3C TTML (Timed Text Markup Language). It was designed for iTunes Store / Apple TV delivery but FCP, Premiere (with a plugin), and Resolve all import it.
Welcome to JianHeBox
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Strengths: Frame-accurate, Apple ecosystem, supports styling and positioning, less brittle than FCPXML.
Limitations: Less universal than SRT, no support in web browsers.
Use iTT when: You're delivering to Apple TV or iTunes Store. You want styled captions in Final Cut Pro. You're working with frame-accurate timing.
TTML is the W3C standard for timed text. It's the most powerful format but also the most complex. DFXP (Distribution Format Exchange Profile) is a profile of TTML used in broadcast captioning.
Use TTML/DFXP when: You're delivering to broadcast (especially US broadcast), you need W3C-standard compliance, or you're integrating with a broadcast workflow system.
SCC is the legacy US broadcast caption format. It encodes CEA-608 data in a plain text file. Frame-accurate but limited styling.
Use SCC when: You're delivering to a US broadcaster that specifically requires CEA-608 captions.
Ask yourself three questions:
The JianHeBox Subtitle Workshop handles SRT, VTT, FCPXML, iTT, TTML/DFXP, SCC, ASS, SUB, SBV, Avid DS, CSV, TSV โ everything you need to move between subtitle formats.