Subtitles tool

Add Subtitles with FFmpeg

Generate FFmpeg commands to burn SRT or ASS subtitles into video, or attach a selectable subtitle track to MP4.

FFmpeg.Run generates commands only. Your media files stay on your computer and are never uploaded.

Quick answer

Burn subtitles when they must always be visible; FFmpeg will re-encode the video. Attach a selectable track when the viewer should be able to turn subtitles on or off; this can preserve the original video stream.

Command options

Presets

Input video

Subtitle file

Output file

Mode

Subtitle format

Style SRT

Font name

Font size

Font color

CRF

Preset

Audio

Generated command

ffmpeg -i "input.mp4" -vf "subtitles=subtitles.srt" -c:v libx264 -crf 23 -preset medium -c:a copy "subtitled.mp4"

Common uses

Burn SRT subtitles permanently into an MP4
Use ASS subtitles with existing styling
Attach selectable subtitles without re-encoding video

How to Add Subtitles to MP4 Using FFmpeg
Add subtitles to MP4 with FFmpeg by burning SRT or ASS subtitles into video. Includes styling, font notes, common errors, and copyable commands.

Related command recipes

Add Subtitles to MP4 with FFmpeg

Burn SRT or ASS subtitles permanently into an MP4 video.

Command notes

Burned-in subtitles use the `subtitles` video filter and require video re-encoding.

Selectable subtitles can be attached with `-c:s mov_text` for MP4 output.

Use `force_style` or ASS subtitles when you need control over font size, color, and styling.

FAQ

Can I add subtitles without re-encoding?

Only if you attach subtitles as a selectable track. Burning subtitles onto the image requires video re-encoding.

Should I use SRT or ASS?

Use SRT for simple subtitles. Use ASS when you need styling, positioning, or effects.

Why do some characters not show?

The subtitle renderer needs a font that supports those characters. Use force_style or an ASS subtitle style with a suitable font.