Use the drawtext filter for simple text on video. If you need more complex timing, formatting, or dynamic text see the subtitles filter. This answer focuses on the drawtext filter.

Example

Print Stack Overflow in white text onto center of video, with black background box of 50% opacity:

ffmpeg -i input.mp4 -vf "drawtext=fontfile=/path/to/font.ttf:text="Stack Overflow":fontcolor=white:fontsize=24:box=1:boxcolor=black@0.5:boxborderw=5:x=(w-text_w)/2:y=(h-text_h)/2" -codec:a copy output.mp4

• The audio is stream copied in this example (like a copy and paste).
• @0.5 controls background box opacity. 0.5 is 50%. Remove @0.5 if you do not want any transparency.
• See the drawtext filter documentation for a complete list and explanations of options.

Preview

You can use ffplay to preview your text without having to wait for a file to encode:

ffplay -vf "drawtext=fontfile=/path/to/font.ttf:text="Stack Overflow":fontcolor=white:fontsize=24:box=1:boxcolor=black@0.5:boxborderw=5:x=(w-text_w)/2:y=(h-text_h)/2" input.mp4

Alternatively you can use mpv but the syntax is slightly different:

mpv --vf="lavfi=[drawtext=fontfile=/path/to/font.ttf:text="Stack Overflow":fontcolor=white:fontsize=24:box=1:boxcolor=black@0.5:boxborderw=5:x=(w-text_w)/2:y=(h-text_h)/2]" input.mp4

Multiple texts

You can chain multiple drawtext filters:

ffmpeg -i input.mp4 -vf "drawtext=fontfile=/path/to/font.ttf:text="Stack Overflow":fontcolor=white:fontsize=24:box=1:boxcolor=black@0.5:boxborderw=5:x=(w-text_w)/2:y=(h-text_h)/2,drawtext=fontfile=/path/to/font.ttf:text="Bottom right text":fontcolor=black:fontsize=14:x=w-tw-10:y=h-th-10" -codec:a copy output.mp4

Position

x and y determine text position:

Repositioning text on demand

You can reposition the text with the sendcmd and zmq filters:

• sendcmd if you have predetermined positions and timing. See Sendcmd in ffmpeg and FFmpeg drawtext filter – is it possible to use variables with live data for x,y coordinates?
• zmq for live, on-the-fly positioning. See ffmpeg cli filter that require user input.

Moving / animated / looping / scrolling text

See:

• ffmpeg moving text drawtext
• Loop text that wipes left to right using FFMPEG drawtext filter
• Scrolling from RIGHT to LEFT in ffmpeg / drawtext

Timing

Use the enable option to control when the text appears.

Show text between 5-10 seconds:

ffmpeg -i input.mp4 -vf "drawtext=fontfile=/path/to/font.ttf:text="Stack Overflow":fontcolor=white:fontsize=24:box=1:boxcolor=black@0.5:boxborderw=5:x=(w-text_w)/2:y=(h-text_h)/2:enable="between(t,5,10)"" -codec:a copy output.mp4

Show text after 3 seconds:

ffmpeg -i input.mp4 -vf "drawtext=fontfile=/path/to/font.ttf:text="Stack Overflow":fontcolor=white:fontsize=24:box=1:boxcolor=black@0.5:boxborderw=5:x=(w-text_w)/2:y=(h-text_h)/2:enable="gte(t,3)"" -codec:a copy output.mp4

Blinking text. For every 10 seconds show text for 5 seconds:

ffmpeg -i input.mp4 -vf "drawtext=fontfile=/path/to/font.ttf:text="Stack Overflow":fontcolor=white:fontsize=24:box=1:boxcolor=black@0.5:boxborderw=5:x=(w-text_w)/2:y=(h-text_h)/2:enable="lt(mod(t,10),5)"" -codec:a copy output.mp4

Random position every 30 seconds:

See ffmpeg – Dynamic letters and random position watermark to video?

Changing / updating text

Add the textfile and reload options for drawtext:

ffmpeg -i input.mp4 -vf "drawtext=fontfile=/path/to/font.ttf:textfile=text.txt:reload=1:fontcolor=white:fontsize=24:box=1:boxcolor=black@0.5:boxborderw=5:x=(w-text_w)/2:y=(h-text_h)/2" -codec:a copy output.mp4

• Update text.txt every time you want the text to change.
• Important: You must update the text file atomically or it may fail. You can do this with the mv command on Linux or macOS.
• If you have many text changes, such as making subtitles, it is easier to make a subtitle file (such as an .ass file via Aegisub) and using the subtitles filter.

Font family instead of font file

You can declare the font family, such as Times New Roman, instead of having to point to a font file. See How to include font in FFMPEG command without using the fontfile option?

Requirements

The drawtext filter requires ffmpeg to be compiled with --enable-libfreetype. If you get No such filter: 'drawtext' it is missing --enable-libfreetype. Most of the ffmpeg static builds available support this: see the FFmpeg Download page for links.