Add an SRT to a Video: Four Ways Compared

Four meanings of "add SRT to video"

An SRT is a separate text file. It doesn't change the video by sitting next to it; something has to read it at playback time or copy it into the picture. People who want to attach subtitles to a video usually want one of four outcomes, and the right method follows from that outcome rather than from whichever tool happens to be open.

Sidecar file

The SRT stays a separate file with the same name as the video. Desktop players such as VLC load it automatically. Viewers can switch it off, and the video itself is unchanged.

Platform upload

YouTube, Vimeo, Facebook and LinkedIn let you upload the SRT alongside the video. The platform shows it as captions viewers can turn on or off, and you can edit the text later.

Muxed track

The subtitles are stored inside the video container as their own stream. One file, still switchable, but whether a given player shows the track varies.

Burned in

The words are drawn into every frame. They show in every app and player, look exactly as styled, and can't be turned off or edited afterwards.

Route one: keep the SRT next to the video

This is the quickest way to watch a downloaded film or a lecture recording with subtitles on your own computer.

1. Put the SRT in the same folder as the video.
2. Give it exactly the same name with the .srt extension, for example lecture-04.mp4 and lecture-04.srt. Some players also understand a language code before the extension, such as lecture-04.en.srt.
3. Open the video in VLC or another desktop player. If the subtitles don't load on their own, add the file from the player's subtitle menu; in VLC that is Subtitle, then Add Subtitle File.

The weakness is obvious: send the video to someone without the SRT and the subtitles are gone. Naming subtitle files covers the conventions players look for, and loading subtitles in VLC has the menu steps in full.

Route two: upload the SRT to the platform

When the video lives on a platform that accepts caption files, upload the SRT there instead of baking it in. Viewers who don't want subtitles can hide them, the platform can index the words, and you can correct a typo later without uploading the video again. On YouTube this happens in YouTube Studio under Subtitles, where you choose the language and upload the file with timing; uploading an SRT to YouTube walks through it, and there are matching guides for Vimeo and Facebook.

The limit is that many places a video ends up have no caption upload at all: messaging apps, most short-video apps and plenty of embedded players. Text that has to be seen there needs route four.

Route three: store the SRT as a track inside the file

Muxing copies the subtitles into the container next to the video and audio streams, so one file carries everything and viewers can still turn the subtitles off. MKV accepts SRT text as it is, and MKVToolNix is the usual free tool for adding it. MP4 stores subtitles in its own timed-text format, so the SRT is converted on the way in. With FFmpeg that is a single command along the lines of ffmpeg -i talk.mp4 -i talk.srt -map 0 -map 1 -c copy -c:s mov_text talk-subs.mp4, which copies the picture and sound untouched. HandBrake can add an SRT as a soft track as well, though it re-encodes the video while doing so.

Muxed tracks make a tidy archive, but support is patchy: desktop players handle them well, while phones, browsers and social apps often ignore the track. The editor on this page doesn't write subtitle tracks into files. Embedded versus sidecar subtitles explains the trade-off, and the HandBrake method is a step-by-step alternative.

Route four: burn the SRT into the picture here

Burning is the route that works everywhere, which is why it is the usual choice for social clips, ads and anything sent through chat apps. The editor on this page does it in your browser:

1. Switch off the AI subtitle option, then choose the video (MP4, MOV, M4V, WebM or MKV).
2. Bring in the SRT with Import SRT / VTT and note how many subtitles the notice reports.
3. Play a few points across the video to confirm the lines match the speech, and fix any that don't.
4. Pick a look in Style, then use Render video and download the new MP4.

The original file isn't touched; you get a second copy with the subtitles in the frames. SRT to MP4 covers this route in depth, including encoding trouble and files timed for a different cut.

Choosing by where the video will be watched

• On your own laptop, from a downloaded file: sidecar. It takes seconds and changes nothing.
• On YouTube or Vimeo: upload the SRT. Viewers keep control, and fixing a line later doesn't mean a new upload.
• In Reels, TikTok, WhatsApp or any feed that autoplays without sound: burn it in, since there is nowhere to put a file.
• As a master you'll keep for years, possibly with several languages: mux into MKV, one track per language.
• On a platform that takes uploads but where many viewers watch muted: some creators burn in one language and upload others as files. Avoid doing both in the same language, or viewers who switch captions on see every line twice.

If you're comparing the soft and permanent options more generally, embedding subtitles in a video untangles what "embedded" means in different tools.

Problems that follow the SRT into every route

Whichever route you choose, the same three faults cause most failures. Encoding comes first: a file saved in an old regional code page shows broken accents in players, on platforms and in this editor alike, so re-save it as UTF-8. Timing is second: an SRT made for a slightly different edit drifts, and no attachment method fixes that; shifting subtitle timing helps when the whole file is early or late by the same amount. Structure is third: missing blank lines, broken timestamps or overlapping lines. Why an SRT file isn't working lists the usual suspects, and checking an SRT for errors shows how the editor flags them.

If you don't have an SRT at all yet, the subtitle generator makes one from the video's speech.

About the subtitle editor on this page

Opens

MP4, MOV, M4V, WebM, MKV videos your browser can decode

Subtitles from

AI (from the speech, optionally translated into one of 21 languages), an SRT or VTT file, or typing them in

You download

An MP4 with the subtitles drawn into the picture at the original resolution and frame rate, plus SRT and VTT files

Cost

Editing, styling, rendering and SRT/VTT export are free, with no account and no watermark. AI subtitles cost 1 credit per minute (5-credit minimum per video); signing in with Google gives 100 free credits and accounts get 10 free credits a day

Privacy

The video never leaves your device and is rendered in your browser. Only for AI subtitles is the audio sent, over HTTPS, and it is deleted within 30 minutes of delivery

Rendering needs

Chrome or Edge 94+, Safari 16.4+, or Firefox 130+ on a computer. Editing and SRT/VTT export work in any current browser