guides · July 2, 2026
SRT vs ASS: which subtitle format do you have?
Subtitle files mostly come in two flavors: SRT and ASS. If you've only ever downloaded a file, dropped it on a player, and watched, you may never have needed to know which one you had. But the moment you translate, edit, or style subtitles, the difference starts to matter.
Telling them apart in five seconds
The file extension usually gives it away — .srt or .ass (occasionally .ssa, the older sibling of ASS). If the extension has been lost or renamed, open the file in any text editor:
SRT is numbered blocks with arrow timestamps:
1
00:00:12,050 --> 00:00:14,200
Where were you last night?
ASS starts with [Script Info] sections and has Dialogue: lines with comma-separated fields:
[Events]
Dialogue: 0,0:00:12.05,0:00:14.20,Default,,0,0,0,,Where were you last night?
If it looks like a config file, it's ASS. If it looks like a list, it's SRT.
What SRT does
SRT is the plain-text workhorse: cue numbers, timings, text, nothing else. That simplicity is its superpower — every player, TV, streaming box, and editing tool on earth reads SRT. The subtitle look (font, size, position) is decided by whatever plays it, not by the file.
Limits: no colors, no positioning, no per-line styling. A line of dialogue and a translated street sign both land in the same spot at the bottom of the screen.
What ASS does
ASS (Advanced SubStation Alpha) carries its own presentation: named styles, fonts, colors, outlines, precise screen positioning, rotations, karaoke timing. This is why anime fansubs are almost always ASS — the format can put a translated sign exactly on top of the sign in the frame, style the opening song in two colors, and keep dialogue in its own clean style at the bottom.
The cost is portability. Support outside desktop players is patchy: VLC and mpv honor ASS styling fully, TVs and streaming devices often don't, and some players fall back to rendering the text plainly.
Does it matter? A practical decision guide
Just watching a film or drama? Doesn't matter. Use whatever file you have; every decent player handles both.
Watching anime with signs and songs? Keep ASS as ASS. Convert it to SRT and every carefully-placed sign collapses into bottom-of-screen text stacked on top of the dialogue — you lose exactly the work that made the fansub good.
Sending subtitles to a TV or an old set-top box? SRT is the safe bet. If all you have is ASS, a conversion is fine when the file is dialogue-only.
Making dual-language subtitles? This is where ASS quietly shines. With two languages in one file, ASS styles can give each language its own size, color, or position — original up top, translation below. In SRT the two languages simply stack in each cue, which works, but reads best when both lines are kept short.
Translating each format
Translating SRT is structurally easy (the timing lives in three lines per cue) — the real work is making the translation fit the screen and the seconds, which we cover in how to translate an SRT file.
Translating ASS has an extra trap: the styling is part of the file. A tool that only understands plain text will strip or scramble the style sections, and the signs, karaoke, and positioning vanish. A proper ASS translation touches only the dialogue text inside each Dialogue: line and leaves every style, tag, and position untouched.
Langelic handles both: upload SRT, ASS, or SSA, and get back the same format with the same timing and styling — only the language changed, reflowed to read at watching speed. ASS styling, signs, and positioning survive the trip.