ffmpegs.pages.dev
That’s been me. Every. Single. Time.
So I built FFmpeg Pages — a dead-simple collection of the commands I kept searching for. No fluff, no digging, just the stuff that actually works.
- The target file size option on the compression tab just changes the bitrate without any consideration for the length of the video. This is immediately visible if you either test the command, if you're aware of what bitrate is, or if you even bother to read the LLM generated code in which there's a comment that says "Assuming 60 second video".
- The resolution options do not allow for anything other than 16:9, you can set one parameter to -1 (or -n for a multiple of n) to make it work with any aspect ratio. I can maybe see a person clumsily missing this one.
- There is no such thing as a "wav" encoder in ffmpeg. This is again immediately obvious if you test the generated commands as ffmpeg will print an error message and not produce an output file.
- Why does the command for "video compression" (which it isn't) in the FAQ not match the command generated by the tool?
The "quality" slider implies that if you move it to the right, you'll get more quality. But higher numbers of the crf value are lower quality, not higher.
The resize function takes no account of the original aspect ratio of the source video, so you'll probably squash things.
Audio extraction ignores whatever the source codec is, missing the opportunity of extracting the source codec without recompressing. Additionally the built-in "aac" codec is very low quality and should not be used. ("libflac" is probably a better choice than "flac", too.)
- For the convert page, the tool seems to conflate codec and container format. For example, for MKV option, the tool specifies libx264, when MKV is capable of many more codecs. In addition, a lot of the times when people want to "convert", e.g. from MP4 to MKV, they mean to remux - i.e. "-c copy", which doesn't seem like an option here.
- For the compress page, the tool allows you to specify the target size, however the command output limits bitrate instead of target size. This means that the output size will vary depending on how long the input is, and will almost never be the specified target size.
I would suggest merge the "Convert" and "Compress" tabs, and allow specifying:
- video bitrate (-b:v)
- video codec (-c:v)
- audio bitrate (-b:a)
- audio codec (-c:a)
- container format
I found handbrake to be a good GUI-based alternative if ffmpeg commands are overwhelming.
For example, something like
> ffmpeg -llm "can you take input.mp4 and resize it to 720p, transcode to vp8 output to output.webm"
> llm -yolo "can you take input.mp4 and resize it to 720p, transcode to vp8 output to output.webm"
separate tools for separate jobs. ffmpeg doesn't need more features.
llm --yolo "combine all the files in videos/vacation in alphabetical order into a single video, do not use the audio from the videos, add the music from music/soundtracks/my-favorite-things.mp3 as background music, but a title at the front 'Our Summer Vacation'"
or something more involved. Yes, it might be able to spit out multiple commands
this website would've been awesome ten years ago.. it'll make great training data now I guess
Way more than that, in fact... I had a bunch of 20-year-old 8mm film transfers on DV, where the scanner had put white-on-black titles between the reels. Claude wrote me a script combining ffmpeg and other tools that not only converted the format from DV to MP4, but found the interstitial titles, did OCR on them, regenerated them in full resolution, replaced the original titles with the new ones, and rendered the result as one file per reel.
+ Compress to target needs to know input length, as others have mentioned. Also, usually I would encode in multiple passes to better allocate the bits if I am targeting a specific size.
+ "Extract audio" shows commands that will reencode the audio stream. If input stream is already in a format that I can use, what I would do is to copy the audio stream without reencoding (`-c:a copy`).
Personally I use AI-shell CLI, type "ai" and ask things like "ffmpeg convert input.mp4 to webm clip first 8 seconds" or any other shell command you need.
Any chance you could add "extract clips" in addition to extract frames? Specifically I had to split a video into x-second clips recently & had to use AI to get the right command for that.
This looks like it could be useful for most people.
> convert this video.mp4 to webm without audio using ffmpeg
$ ffmpeg -i video.mp4 -c:v libvpx -an output.webm
a few batch files
for all common tasks
names starting with ffmpeg.*
and -h displays help.