Convert plain text to a timed SRT subtitle file in your browser. Paste your script, set timing rules, preview the cues and download your .srt — free.
AI-powered audio review & delivery for voice production teams
Paste or load some text to see your subtitle cues here.
An SRT (SubRip Subtitle) file is just a plain-text file with a .srt extension, made of numbered cues. Each cue has three parts on consecutive lines: a sequential index, a start and end timestamp, and one or two lines of caption text. A blank line separates each cue from the next. That is the entire format — which is why you can make an SRT file from any text, as long as you add the timing. This converter generates that timing for you and writes the file in the exact shape players expect.
Timestamps use the form HH:MM:SS,mmm — hours, minutes, seconds and milliseconds, with a comma before the milliseconds (not a period — that is the most common reason an SRT fails to load). Start and end are joined by a space-arrow-space: -->. A single cue looks like this:
1
00:00:00,000 --> 00:00:02,000
Welcome to the show.
2
00:00:02,100 --> 00:00:05,400
Today we're talking
about subtitles.
Cues are numbered 1, 2, 3… with no gaps, in time order. Keep captions to one or two lines so they fit on screen; this tool wraps text to your chosen line length and never puts more than your maximum number of lines in a cue. SubRip files use CRLF line endings, which is what the download here produces.
Save SRT files as UTF-8 so accented characters, non-Latin scripts and emoji survive. The file you download is UTF-8 encoded, so anything you paste — including 🎬 or “smart quotes” — is preserved exactly. Once you have your SRT you can convert it to WebVTT for HTML5 video with a dedicated srt-to-vtt-converter, or run it through an srt-validator to catch overlaps and numbering gaps.
| Setting | Recommended value | Why |
|---|---|---|
| Reading speed | ~17 characters/second | Roughly 160–180 words per minute — comfortable to read |
| Cue duration | 1–7 seconds | Long enough to read, short enough to stay in sync |
| Characters per line | ~42 | Fits on phones and TVs without truncation |
| Lines per cue | 1–2 | More than two lines covers too much of the screen |
Paste your transcript or script above (or load a .txt file), choose whether each line is its own caption or the text should be auto-split by sentence, then set a reading speed and line length. The tool builds numbered, timed cues and lets you download a ready-to-use .srt. No software to install and nothing is uploaded.
A good rule of thumb is a reading speed of about 17 characters per second (roughly 160–180 words per minute), with each cue on screen for at least 1 second and no more than about 7 seconds. This converter derives every cue's duration from your chosen characters-per-second value and clamps it to that 1–7 second range, then leaves a small gap before the next cue so they don't run together.
Most broadcasters and streaming platforms cap subtitle lines at around 42 characters, on a maximum of two lines per caption. That keeps text comfortably on screen on phones and TVs alike. The default here is 42 characters over up to 2 lines; the preview highlights any line that runs over your limit so you can tighten the text or raise the cap.
SRT (SubRip) is the most widely supported subtitle format — it works in VLC, Premiere Pro, DaVinci Resolve, YouTube and most TVs. WebVTT (.vtt) is the format HTML5 video uses in the browser; it starts with a WEBVTT header and uses a period before the milliseconds instead of a comma. If you need VTT for a website player, make your SRT here first and then run it through a dedicated srt-to-vtt-converter.
VoiceDeck adds AI-powered audio & video review and delivery for your whole team — so every file ships in spec, automatically.