How to make an SRT file (and the format rules that break players)

An SRT file is a plain text file where each subtitle is a number, a time range, one or two lines of text, and a blank line. You can make one in any text editor, export one from a transcription tool, or convert a transcript with a free subtitle editor. Most files that get rejected by YouTube or a video player fail on one of five details: a full stop instead of a comma in the timestamps, a missing blank line, the wrong text encoding, overlapping times, or styling tags the player does not understand.

The format, exactly

Here is a complete, valid SRT file with two subtitles:

1
00:00:04,000 --> 00:00:07,400
Thanks for making the time.

2
00:00:07,480 --> 00:00:11,200
I want to start with the part
you said was messy.

Four rules produce it:

1. A counter. Each subtitle starts with a whole number on its own line, counting up from 1.
2. A time range. Hours, minutes, seconds and milliseconds, written HH:MM:SS,mmm, then a space, an arrow made of two hyphens and a greater-than sign, a space, and the end time. The separator before the milliseconds is a comma. The format comes from a French program and French decimal notation uses commas.
3. The text. One or two lines. A third line works in some players and is cut off in others.
4. A blank line. It ends the subtitle. The blank line is not decoration; it is how players find the next counter.

Save it as plain text with the extension .srt, encoded as UTF-8.

Three ways to make one

1. Export it from a transcription tool

The fastest route. Our transcriber runs on your computer and writes the SRT for you: drop the audio or video file on the home page, wait for the transcript, and press the .srt button. The cues are built to the timing rules below, and nothing is uploaded on the way. Make an SRT from your own file.

Any transcription service will export SRT too. The thing to check is whether the export splits long sentences into readable cues or dumps a whole paragraph into one subtitle. A paragraph is valid SRT and unreadable on screen.

2. Write it by hand

For a short clip, a text editor is fine. Play the video, note when each line starts and ends, and type the four-line blocks. Two habits save time: keep every timestamp as eight digits plus three, even for hours you never reach (00:01:05,000, not 1:05), and leave a blank line after every block including the last.

Use a plain-text editor: Notepad, TextEdit in plain-text mode, VS Code, or anything that does not add formatting. Word processors insert curly quotes and hidden characters that some players choke on.

3. Convert a transcript

If you have the words but not the timing, a free subtitle editor does the alignment. Subtitle Edit on Windows and Aegisub on every platform both open a plain text file, let you set cue times against the audio waveform, and save as SRT. This is also the tool to reach for when an exported SRT needs its timing nudged.

Timing rules that make subtitles readable

A valid file and a readable file are different things. The public style guides broadcasters use agree on a few numbers, and they are worth adopting even for a YouTube clip.

• 42 characters per line, two lines maximum. Netflix’s English timed-text style guide uses exactly these limits. Longer lines get cut off on phones and TVs.
• Reading speed around 20 characters per second for adults, 17 for children’s content, again from the Netflix guide. A cue with 60 characters needs at least three seconds on screen.
• Break lines at natural points. After punctuation, before conjunctions, before prepositions. Do not split a first name from a last name, or an article from its noun.
• Leave a gap between cues. Two or three frames, roughly 80 to 120 milliseconds. Cues that touch flicker; cues that overlap are invalid in some players.
• Keep each cue between about one and six seconds. Under a second flashes; over six or seven seconds means the cue should have been two.

Our exporter follows these: 42 characters, two lines, one to six seconds, an 80-millisecond gap.

Five mistakes that break the file

A full stop in the timestamp. 00:00:04.000 is WebVTT, not SRT. Some players accept both; YouTube and several editors reject the file. Use a comma.

A missing blank line. Without the blank line between blocks, the player reads the next counter as a line of text and the subtitles drift by one from then on.

The wrong encoding. Files saved as Windows-1252 or Latin-1 turn accented letters and curly apostrophes into é and ’. Save as UTF-8. YouTube states that SRT uploads must be plain UTF-8. Leave the byte-order mark out; a few older players show it as a stray character at the start of the first subtitle.

Overlapping or backwards times. A cue that ends after the next one starts, or an end time before its start time, is silently dropped by some players and rejected outright by others. Subtitle editors flag these; a text editor does not.

Styling tags. <i>, <b> and font tags work in VLC and some desktop players. YouTube ignores all markup in SRT and treats the file as plain text, so tags either vanish or appear literally. If you need styling, use WebVTT or the platform’s own caption editor.

Checking the file

Open the video in VLC, drag the SRT onto the window, and scrub through three places: the start, the middle and the end. If the start is right and the end is late, the video’s frame rate does not match what the SRT was timed against, and a subtitle editor can stretch the timing. If everything is offset by the same amount, most players let you shift subtitles with a keyboard shortcut, and the editor can save the shifted file.

For YouTube, upload the file under Subtitles for the video and use the preview before publishing. YouTube recommends SubRip or SubViewer for anyone starting out precisely because the files are plain text you can fix by hand.

Frequently asked questions

What does SRT stand for? SubRip Text. SubRip was a program that extracted subtitles from DVDs, and its output format outlived it.

Is SRT the same as VTT? Nearly. WebVTT adds a WEBVTT header, uses a full stop before milliseconds, makes the counters optional, and supports styling. Browsers require VTT for HTML video; almost everything else accepts SRT. Which export do you need covers when to use each.

Can an SRT file have more than two lines per subtitle? The format allows it. Players and platforms do not agree on what to do with the third line, so keep to two.

Does the counter have to be sequential? Most players ignore the number, but some validators require it to count up from 1 without gaps. Renumber after editing; subtitle editors do it automatically.

How long can an SRT file be? There is no limit in the format. A three-hour recording produces a few thousand cues and a file under a megabyte.

Sources, checked 14 September 2026

• YouTube Help, “Supported subtitle and closed caption files”: support.google.com/youtube/answer/2734698
• Netflix Partner Help, “English Timed Text Style Guide”: partnerhelp.netflixstudios.com
• Our own cue-building rules in the transcriber’s exporter, which you can read on this site