A separate subtitle file only works when the player loads it. Upload a video to a social network, send it in a chat app or play it from a phone's gallery, and the SRT next to it is usually ignored. Most short videos are watched with the sound off, so a clip without visible captions loses much of its audience in the first seconds.
Burning, also called hardcoding, solves that by drawing the text into the frames themselves. Add your video, choose its subtitle file, pick a text size and a style, and press Convert. The result is an MP4 in which the subtitles are part of the picture, made entirely in your browser.
Burned-in subtitles versus subtitle files
Soft subtitles are a separate text track or file. Viewers can switch them on and off, choose between languages, and the player decides how they look. Burned-in subtitles, also called open captions, are pixels in the video like everything else: they cannot be switched off, translated or restyled after the fact, but they look the same on every screen and need no player support at all.
That makes burning the right choice for social media clips, videos shared through messengers, presentations played from a laptop, and anywhere you cannot be sure a subtitle file will be loaded. Keep the original video and the subtitle file as well, because once text is burned in, the only way to change it is to burn again from the clean source.
When hardcoded subtitles are the better choice
Clips for Instagram, TikTok and other feeds
Feeds autoplay without sound. Burned-in captions let people follow what is said from the first frame, without depending on the platform's own captioning.
Translated versions for a specific audience
A video with burned-in Spanish, French or Russian subtitles can be shared as a single file that plays the same everywhere.
Accessibility in places without caption support
Kiosks, digital signage, some conference systems and older TVs play video files but ignore subtitle tracks. Open captions make the content accessible there too.
Fonts, styles and how the subtitles are drawn
The subtitle file can be SRT, VTT or SBV, in UTF-8, UTF-16 or an older Windows encoding; it is read with the same careful decoding as the SRT to VTT converter and turned into SRT before drawing. Text is set in white Liberation Sans Bold, centred near the bottom of the frame. Text size offers Small, Medium and Large, and the size scales with the video's height, so Medium looks similar on a 720p and a 4K clip. Style offers Outlined, with a black outline and a soft shadow that stays readable on most backgrounds, and Dark box, a semi-transparent dark band behind the text for busy or bright footage.
The font covers Latin, Greek and Cyrillic letters. Arabic, Hebrew, Chinese, Japanese, Korean, Hindi, Thai and other scripts are not supported yet and would appear as empty boxes, because the in-browser converter has no other fonts to fall back on. Drawing text means every frame is re-encoded, so the output is an H.264 MP4 with AAC sound whatever the input format, named with -subtitled. The work is done by ffmpeg running as WebAssembly, a one-time download of about 31 MB.
طريقة الاستخدام
- Drop one or more MP4, MOV, WebM, MKV or AVI videos on the box above.
- Under Subtitle file (SRT, VTT or SBV), press Choose file and pick the subtitles. The same file is used for every video in the queue.
- Choose a Text size (Small, Medium or Large) and a Style (Outlined or Dark box).
- Press Convert, check the result in a player and download the MP4.
Limitations
- Only Latin, Greek and Cyrillic scripts can be drawn for now.
- Positions and styling from VTT cue settings are not used; every subtitle appears at the bottom centre in the chosen style.
- Colour, font and exact position cannot be changed.
- Burned subtitles cannot be removed or switched off later. Keep the original video.