Add SRT to video
and burn it into the MP4.
Drop your subtitle file to see its lines in real caption styles, then add your video and export with the subtitles burned in.
Drop an .srt, .vtt or .ass file here
Your subtitle file comes with you; in the editor you only pick the video. Nothing is transcribed, so no minutes are used. Previewing and restyling is free. Exporting the MP4 with burned-in subtitles is part of Pro ($5/month).
Soft subtitles vs burned-in subtitles
An MP4 can carry an SRT as a separate track that players like VLC let you switch on and off. TikTok, Instagram, YouTube Shorts, X and WhatsApp drop that track on upload, so viewers never see it. Burning the subtitles in draws them into each frame, which is the only way they survive every upload.
The preview above uses the same renderer as the export, so a line that fits here fits in the final MP4. Lines above 17 characters per second are flagged: most viewers can't finish reading them before they disappear.
Frequently asked
How do I add an SRT file to an MP4?+
There are two ways. A soft subtitle track (muxing) keeps the SRT as a separate track the viewer can switch off, which needs a player that supports it. Burning in (hardcoding) draws the text into the video frames, so it shows everywhere: TikTok, Instagram, WhatsApp, LinkedIn and any player. Social platforms ignore soft tracks, so for short-form video you want to burn in.
Does adding my own SRT use transcription minutes?+
No. When you bring a subtitle file the editor takes the text and timing from it and skips speech recognition entirely, so your free or Pro transcription minutes stay untouched.
Is it free?+
Previewing your file, restyling it and downloading SRT or VTT are free. Exporting the MP4 with the subtitles burned in is part of Pro ($5/month, 100 export minutes a month, no watermark).
Which subtitle formats work?+
SRT, WebVTT (.vtt) and ASS/SSA. Styling tags inside the file (italics, ASS override blocks, colours) are removed and the caption style you pick in the editor is applied instead, so every line looks consistent.
My subtitles are out of sync with the video. What now?+
If every line is early or late by the same amount, shift the whole file with the subtitle timing shifter first. If the drift grows over time, the file was made for a different frame rate; fix it with the frame-rate converter.
Can I do this with ffmpeg or HandBrake instead?+
Yes. ffmpeg burns an SRT with -vf subtitles=subs.srt and HandBrake has a Burn In checkbox in its Subtitles tab. Both render plain white text; styling means writing ASS by hand. SoCaptions is the visual route: pick a style, see it on your video, export.