Work with videos,without the complexity.

No, and for video that matters more than for almost any other file type. A video is large enough that uploading it is slow, expensive in data and a genuine privacy event, and the encoding engine here is downloaded once and then runs entirely on your own device. A holiday recording, a family video or an unreleased work presentation is personal material, and this way the content never crosses the network.

Almost always because of the container rather than the clip itself. A phone records a large file in a format that a messaging app, an email provider or an upload portal will refuse, slow to a crawl, or silently re-encode into something worse than the original. Converting to the format the destination actually wants resolves that, and there is no upload phase, so the conversion starts immediately.

No. There is no account to create, no email address to hand over and nothing to install, because the encoding engine ships as part of the page itself. Chrome, Edge, Firefox and Safari are all supported, on a desktop or a phone, and the interface adapts to the screen you are using.

Bitrate, and the relationship between bitrate and perceived quality is not linear. Doubling the bitrate makes the video twice as large, not twice as good. Most viewers notice the difference between a low bitrate and a moderate one very clearly, while the difference between moderate and high is difficult to see on an ordinary screen, which makes the highest setting a poor default even though it is the one people reach for first.

Resolution should match the smallest screen the video will be seen on, and this is the single most effective change available. A 4K video watched on a phone looks no better than a 1080p version, takes several times as long to load on a mobile connection, and is the usual reason a message fails to send. Reducing resolution accounts for most of the saving and does so more effectively than any reduction in bitrate at the same target size.

When the material is intended for a large screen or a projector, where the reverse logic applies and reducing resolution is the first thing to avoid. Otherwise, match the output to the smallest screen it will realistically be viewed on. Scaling a video up gains nothing and costs file size, because upscaling a low resolution source does not add real detail.

A short clip completes in moments, but video contains far more data than an image or audio file and every frame has to be decoded and re-encoded, so a long recording takes proportionally longer and on a phone it can take several minutes. Keep the tab open and in the foreground until the download starts, because a backgrounded tab may be throttled by the browser and take considerably longer for no benefit.

It depends on your device, because very long videos need a great deal of free memory and may not process at all in a tab. Converting in sections is the better workflow anyway: it lets you confirm the settings on the first minute before committing to the whole file, and produces pieces that are easier to upload individually if the destination is awkward.

No. The content is left as it is, with no trimming, cropping, filtering, stabilisation, colour correction or audio enhancement applied, so a recording that needs editing still needs editing afterwards. The tool changes the container and the encoding; it does not change what the video shows. Subtitle tracks and chapter markers may also not be carried across, depending on the source and the target format.

Because a video is expensive to record and impossible to re-shoot, and a conversion that does not look right is much better discarded and retried than worked around. DRM-protected and streaming-only files cannot be read at all, since they are encrypted or delivered in a way that deliberately prevents copying.