How to Cut or Trim a Video with FFmpeg

FFmpeg can cut a clip from a longer video in two main ways. Use stream copy when you want speed and no quality loss. Use re-encoding when you need a frame-accurate cut.

For the short command page, see Cut Video with FFmpeg. For a form-based command builder, use the Cut Video tool.

Fast Trim Without Re-encoding

ffmpeg -ss 00:01:00 -i input.mp4 -t 00:00:30 -c copy clip.mp4

This creates a 30-second clip starting at 1 minute. Because it uses -c copy, FFmpeg copies the existing audio and video streams instead of re-encoding them.

Use this when:

• You want the fastest possible trim.
• You want to avoid quality loss.
• You do not need the cut to start on the exact frame.

Cut by Start and End Time

Use -to when it is easier to think in start and end timestamps:

ffmpeg -ss 00:01:00 -to 00:02:00 -i input.mp4 -c copy clip.mp4

This keeps the section from 00:01:00 to 00:02:00.

Accurate Trim

If the fast command starts a little early, shows a black frame, or has artifacts at the beginning, re-encode the clip:

ffmpeg -ss 00:01:00 -i input.mp4 -t 00:00:30 -c:v libx264 -crf 23 -preset medium -c:a aac clip.mp4

This is slower, but it gives FFmpeg the freedom to decode and encode the exact segment.

What the Options Mean

Option	Meaning
-ss 00:01:00	Start time for the trim.
-t 00:00:30	Duration of the output clip.
-to 00:02:00	End timestamp for the clip.
-c copy	Copies streams without re-encoding.
-c:v libx264	Re-encodes video as H.264 for accurate cuts.
-c:a aac	Re-encodes audio as AAC for MP4 compatibility.

Where to Put -ss

Putting -ss before -i is usually faster:

ffmpeg -ss 00:01:00 -i input.mp4 -t 00:00:30 -c copy clip.mp4

Putting -ss after -i can be more accurate when re-encoding, but it may be slower:

ffmpeg -i input.mp4 -ss 00:01:00 -t 00:00:30 -c:v libx264 -crf 23 -c:a aac clip.mp4

For most users, start with -ss before -i.

Common Problems

The clip starts a few seconds early.
That is a keyframe limitation of -c copy. Use the accurate re-encode command.

The beginning has a black screen or artifacts.
Use re-encoding instead of stream copy.

The output has no audio.
Check that the input has an audio stream. If the source audio is unusual, use -c:a aac.

The file is larger than expected.
If you re-encode, increase CRF from 23 to 25 or 28.

Related FFmpeg Pages

• See the short recipe: Cut Video with FFmpeg.
• Build a custom command with the Cut Video tool.
• Build format conversion commands with the Convert Video tool.
• Learn how to create a GIF from a video clip.