What an SRT file is and why you need one

An SRT file is a plain text document that holds subtitles for a video. SRT stands for SubRip, which is the format name. The file contains the subtitle text, the time codes that tell the video player when each subtitle should appear and disappear, and a sequence number for each subtitle block. Video players like VLC, Windows Media Player, and most streaming software can read SRT files without any special software.

You create an SRT file when you want to add subtitles to a video you've made, or when you want to translate subtitles from one language to another. The file itself is just text — you can open it in Notepad, Word, or any text editor. The video player reads the SRT file alongside the video file and displays the text at the right moments.

Key Takeaways

  • An SRT file is a text document with three parts per subtitle: a number, a time code showing when the text appears and disappears, and the subtitle text itself.
  • You write SRT files in any text editor like Notepad, and save the file with the .srt extension in the same folder as your video.
  • Time codes must follow the exact format HH:MM:SS,mmm (hours, minutes, seconds, milliseconds) with a comma before the milliseconds, not a period.
  • The video player will only find your SRT file if it has the same name as the video file — for example, movie.mp4 and movie.srt.

The three parts of every subtitle block

Each subtitle in an SRT file has the same structure. First comes a number — just 1, 2, 3, and so on in order. This number tells the video player which subtitle comes first, second, and third. The numbers don't have to be consecutive (you could use 1, 2, 5 if you wanted), but they must be in order from top to bottom.

Second comes the time code line. This line has two time stamps separated by an arrow made of two dashes and a greater-than sign: 00:00:05,000 --> 00:00:10,500. The first time stamp is when the subtitle appears. The second is when it disappears. Both must follow the format HH:MM:SS,mmm — hours, minutes, seconds, and milliseconds. The milliseconds use a comma, not a period. If your subtitle should appear at 5 seconds and disappear at 10 and a half seconds, you write 00:00:05,000 --> 00:00:10,500.

Third comes the subtitle text itself. You can write one line or multiple lines. The video player will display exactly what you type here. After the text, you leave one blank line before the next subtitle block begins. That blank line is how the player knows one subtitle has ended and the next one is starting.

Step-by-step: creating your first SRT file

Open Notepad (on Windows, search for "Notepad" in the Start menu; on Mac, open Applications > Utilities > TextEdit and set the format to plain text). Type your first subtitle block exactly like this:

1 00:00:05,000 --> 00:00:10,500 This is the first subtitle

Press Enter twice to create a blank line, then type your second subtitle:

2 00:00:11,000 --> 00:00:15,800 This is the second subtitle

Continue adding subtitles until you've entered them all. Each block needs the number, the time code, the text, and a blank line after it. The last subtitle does not need a blank line after it.

When you're done, go to File > Save As. Name the file exactly the same as your video file, but with .srt at the end instead of .mp4 or .mov or whatever your video uses. If your video is called "birthday_party.mp4", name the SRT file "birthday_party.srt". Save it in the same folder as the video. The video player will find it automatically when you open the video.

Getting the time codes right

The hardest part of making an SRT file is figuring out the exact times when each subtitle should appear and disappear. You need to watch the video and note the time for each line of dialogue or text you want to subtitle.

Most video players show the current time in the bottom left or bottom right corner. VLC (a free player available at videolan.org) shows the time clearly and lets you pause and rewind easily. Play the video, pause it at the moment a character starts speaking, and write down the time shown. Then play forward until the character finishes speaking, pause again, and write down that time. Use those two times for your time code line.

If you're working with a video editor like DaVinci Resolve (free) or Adobe Premiere, the timeline at the bottom shows exact time codes. You can hover over the timeline to see the precise moment each line of dialogue begins and ends. Write those times down and transfer them to your SRT file.

Be precise but don't obsess over milliseconds. A subtitle that appears 100 milliseconds early or late won't bother viewers. What matters is that the subtitle appears before the character starts speaking and disappears after they finish.

Common mistakes that break SRT files

The most common error is using a period instead of a comma in the time code. 00:00:05.000 --> 00:00:10.500 looks right but won't work. It must be a comma: 00:00:05,000 --> 00:00:10,500. Video players are strict about this.

The second mistake is forgetting the blank line between subtitle blocks. If you type one subtitle and when ready start typing the next number without a blank line, the player will get confused and may skip subtitles or display them incorrectly.

The third mistake is saving the file with the wrong name or in the wrong folder. If your video is "wedding.mp4" and you save the SRT file as "wedding_subtitles.srt", the player won't find it. The names must match exactly (except for the file extension). Both files must be in the same folder.

The fourth mistake is saving the file as .txt instead of .srt. When you save in Notepad, the default is to add .txt to the end. You must change it to .srt, or tell Notepad to save as "all file types" so it doesn't add anything automatically.

Using SRT files with different video players

Once you've created your SRT file and saved it with the correct name in the correct folder, most players will load it automatically. VLC, Windows Media Player, and QuickTime all recognize SRT files without any extra steps.

Some players require you to manually load the subtitle file. If you open your video and no subtitles appear, look for a menu option like "Subtitles" or "Load Subtitle File". Click it and select your SRT file from the folder. The subtitles should appear when ready.

If you're uploading a video to YouTube, Vimeo, or another platform, you can usually upload the SRT file separately in the video settings. YouTube calls this "Closed Captions" and has its own upload tool. The platform will display your subtitles to viewers who turn them on. Check the platform's help section for the exact steps, as each one is slightly different.

Frequently Asked Questions

Can I edit an SRT file after I create it?

Yes. Open the SRT file in any text editor, make your changes, and save it. You can fix typos, adjust time codes, add or remove subtitles, or change the text. The video player will use the updated file the next time you open the video.

What if my time codes are off by a few seconds?

You can adjust them. Open the SRT file and change the time codes to match the video better. If every subtitle is 2 seconds too early, add 2 seconds to every time code. If some are early and some are late, fix them individually. Save and test with the video player.

Can I use SRT files with videos on my phone?

It depends on the app. Some phone video players recognize SRT files if they're in the same folder as the video. Others don't support external subtitle files at all. Check your phone's video player documentation, or try uploading the video to a platform like YouTube that handles subtitles for you.

Do I need special software to create an SRT file?

No. Notepad or any text editor is enough. If you're creating subtitles for many videos or working with a team, subtitle editing software like Subtitle Edit (free) or Aegisub (free) makes the job faster because they let you play the video and click to set time codes instead of typing them manually.

What's the difference between SRT and other subtitle formats?

SRT is the most widely supported format and works with almost every video player. Other formats like VTT, ASS, and SUB exist but are less common. For most purposes, SRT is the safest choice because it's straightforward and compatible everywhere.