Audio & Video Tools
Trim, convert and extract audio and video — locally.
Coming soon
The first tools in this category are in development. In the meantime, browse everything that is already live.
About Audio & Video Tools
Audio and video are the file types most likely to be too large, in the wrong format, or longer than you need. A voice memo that needs to become an MP3. A clip that needs its first thirty seconds removed. A video that needs to become a GIF.
These tools convert between audio formats, trim and cut clips, extract audio tracks from video, turn video into animated GIFs, and record audio directly from your microphone.
Media processing is genuinely demanding, and running it in a browser is only recently practical. These tools use a WebAssembly build of FFmpeg — the same engine behind most desktop media software — compiled to run locally. That means real format support and real quality, but it also means a larger initial download and processing that depends on your device's speed. Expect a short wait when a media tool first loads, and expect longer files to take proportionally longer.
The tradeoff is worth it for the same reason as everywhere else on this site: your recordings never leave your device. Voice memos, meeting recordings, and personal video are among the most sensitive files most people handle, and uploading them to a free conversion site to save ninety seconds is a poor trade.
Containers, codecs, and why the extension lies
A file ending in .mp4 tells you almost nothing about what is inside it. MP4 is a container — a wrapper describing how streams are arranged — while the actual compression is done by a codec such as H.264, H.265 or AV1 for video, and AAC or MP3 for audio. Two .mp4 files can be entirely different internally, which is why one plays on a device and another does not.
This explains a common frustration: converting a file to .mp4 does not guarantee it will play, because the player may lack the codec inside. It also explains why some conversions are near-instant while others take minutes. Changing the container while keeping the streams — remuxing — is fast, since nothing is re-encoded. Changing the codec means decoding and re-compressing every frame.
Why browser media processing is slower
Desktop media software uses your machine's dedicated video hardware, which is built specifically for encoding and decoding. Browser-based processing runs FFmpeg compiled to WebAssembly on the CPU, without access to that hardware, and typically runs several times slower as a result. The engine also has to download before anything happens — around thirty megabytes on first use, cached thereafter.
The practical guidance: these tools suit short clips, voice memos and social-length video rather than hour-long recordings or 4K footage. Keep the tab in the foreground while processing, since browsers throttle background tabs. For anything long or high-resolution, desktop software remains the better choice — and every re-encode loses a little quality, so trim before converting rather than after.
Frequently asked questions
Why do media tools take longer to load than the rest of the site?
They download a WebAssembly build of FFmpeg, roughly thirty megabytes, the first time you use one. That is the engine doing the actual work, and it is why real format support is possible in a browser at all. It is cached afterwards, so subsequent visits load normally.
Are my recordings uploaded for processing?
No. Everything is processed on your device by FFmpeg running locally in your browser. This is the reason these tools exist — voice memos, meeting recordings and personal video are among the most sensitive files people own, and free conversion sites routinely upload them to servers you cannot inspect.
How long a file can I process?
There is no hard limit, but processing runs on your CPU without access to video hardware, so it is several times slower than desktop software. Short clips, voice memos and social-length video work comfortably. Hour-long recordings or 4K footage are better handled by a desktop application. Keep the tab in the foreground, since browsers throttle background tabs.
Will converting reduce quality?
Usually yes, slightly. Re-encoding decodes and re-compresses every frame, and lossy formats lose a little detail each time — so repeated conversions accumulate damage. Trim before converting rather than after, keep your original, and use the highest quality setting you can accept. Format changes that only swap the container, without re-encoding, are lossless and fast.