SRT files are the most widely used subtitle format in the world. Learn what SRT files are, how they work, how to open them, and how to edit them for free.
What Is an SRT File? Everything You Need to Know
If you've ever downloaded a movie, uploaded a video to YouTube, or worked with captions, you've almost certainly encountered an SRT file. They're everywhere — and for good reason. SRT is the most universally supported subtitle format in the world.
Here's everything you need to know about SRT files — what they are, how they work, and what you can do with them.
What Does SRT Stand For?
SRT stands for SubRip Text. The format was created by a Windows program called SubRip, which could "rip" (extract) subtitles from DVDs. The format became so widely adopted that it's now the industry standard for subtitle files.
What Is an SRT File?
An SRT file is a plain text file that contains subtitle information for a video. It stores:
- Cue numbers — a sequential number for each subtitle entry
- Timestamps — when each subtitle should appear and disappear
- Subtitle text — the actual words displayed on screen
The file extension is .srt.
What Does an SRT File Look Like?
Here's a simple example:
1
00:00:01,000 --> 00:00:04,000
Hello and welcome to this video.
2
00:00:05,500 --> 00:00:09,000
Today we're going to talk about subtitle formats.
3
00:00:10,000 --> 00:00:13,500
Let's get started.
Each block has three parts separated by blank lines:
- The cue number
- The timestamp (
HH:MM:SS,mmm --> HH:MM:SS,mmm) - The subtitle text (can be one or multiple lines)
What Programs Can Open SRT Files?
SRT files are plain text, so you can open them with:
- Any text editor — Notepad, TextEdit, VS Code, Sublime Text
- VLC Media Player — load alongside a video for instant subtitles
- Video editing software — Premiere Pro, DaVinci Resolve, Final Cut Pro
- YouTube — upload directly as a caption file
- Netflix / streaming platforms — standard format for caption submissions
How Do SRT Files Work With Video?
SRT files are separate from the video file. When you play a video in VLC or another player, you load the SRT file alongside it, and the player reads the timestamps to display the correct subtitle text at the right moment.
On platforms like YouTube, you upload the SRT file separately in the caption settings, and YouTube handles the synchronisation automatically.
How to Edit an SRT File
Since SRT is plain text, you can edit it in any text editor. Common edits include:
- Fixing typos — just find and edit the text
- Adjusting timing — change the timestamps manually
- Adding or removing cues — add or delete blocks and renumber
For more complex edits, use our free online tools:
- Subtitle Time Shifter — shift all timestamps forward or backward at once
- Subtitle Merger — combine multiple SRT files into one
- Subtitle Splitter — split one large SRT file into parts
- Subtitle Overlap Fixer — automatically fix overlapping cues
SRT vs Other Subtitle Formats
| Format | Best For | |---|---| | SRT | Universal use — video players, YouTube, editing software | | VTT | Web video — HTML5 players, Vimeo | | ASS/SSA | Advanced styling — anime subtitles | | SBV | YouTube's native format | | DFXP/TTML | Broadcast and enterprise |
For most purposes, SRT is the right choice. If you need VTT for web use, you can convert SRT to VTT instantly for free.
Common SRT File Problems and How to Fix Them
Subtitles are out of sync
The timestamps don't match the video. Use our Subtitle Time Shifter to shift all timestamps forward or backward by a set amount.
Subtitles overlap
Two cues have conflicting timestamps. Use our Subtitle Overlap Fixer to detect and resolve all overlaps automatically.
Wrong encoding / garbled characters
SRT files should be saved in UTF-8 encoding. Open the file in a text editor and re-save it as UTF-8.
Player won't load the SRT file
Check that the SRT file has the same name as the video file (just with a different extension) and is in the same folder. Most players auto-detect subtitle files this way.
Frequently Asked Questions
Are SRT files free to use?
Yes. SRT is an open format with no licensing restrictions.
Can I create an SRT file from scratch?
Yes — just open a text editor and follow the format: cue number, timestamp, text, blank line, repeat. Save the file with a .srt extension.
What's the maximum file size for an SRT file?
There's no official limit. SRT files are plain text so they're very small — a two-hour film's subtitles might only be 100-200KB.
Do SRT files support styling?
SRT has limited styling support. You can use basic HTML-like tags such as <b>, <i>, and <u> in some players. For advanced styling, use VTT or ASS format instead.
How do I add an SRT file to a video permanently?
This is called "hardcoding" or "burning in" subtitles. You need video editing software or a tool like HandBrake to embed the subtitles permanently into the video file.
Summary
SRT is the most widely supported subtitle format in the world — simple, universal, and easy to edit. If you need to work with SRT files — whether converting, timing, merging, or fixing — all our tools are free to use right in your browser: