CanDoYaRuns entirely in your browser - no upload, no sign-up.
Your source and result stay in this browser tab. The video is never uploaded.
A video compressor reduces video file size by re-encoding the picture and audio with more efficient settings. Choose a local video, select quality, resolution, and MP4 or WebM output, then download the smaller result. Processing runs in your browser, so the video is not uploaded or watermarked.
This compressor loads a WebAssembly build of FFmpeg only when you start processing. MP4 output uses H.264 video with AAC audio for broad playback support. WebM uses VP9 and Opus for modern browsers. Both modes remove source metadata from the new file.
Compression is not lossless. The encoder removes visual detail that is harder to notice, and downscaling removes pixels. Results vary with motion, grain, duration, source codec, and how efficiently the original was already encoded.
No. The selected video is read from a local browser file object and processed by a WebAssembly video engine in this tab. The engine files download on first use, but your source and compressed result are not sent to that server or stored in a CanDoYa account.
Yes. You can compress, preview, and download videos without an account, subscription, credit limit, or watermark. Practical limits come from available browser memory and processing speed. This tool applies a conservative limit based on the device, from 100 MB on lower-memory devices to 500 MB on high-memory desktops.
There is no fixed percentage because results depend on the source codec, resolution, motion, noise, duration, and previous compression. A high-resolution or lightly compressed source may shrink substantially. An efficient source can stay similar in size or even grow, so the tool reports the exact result instead of promising a target.
Re-encoding to a smaller file is normally lossy, even when the change is hard to see. Keep source resolution and choose Higher quality for the least visible change. For a much smaller file, Balanced quality at 720p is a useful starting point, but always preview detailed text, faces, and fast motion.
Choose MP4 for the widest compatibility with phones, messaging apps, presentation software, and older devices. Choose WebM when the video will play in a modern browser and you want VP9 compression. A source file's container does not restrict the output, but uncommon input codecs may fail to decode in some browsers.
The browser decodes and re-encodes every frame on your device. Long, high-resolution video requires much more work and memory than a short 720p clip, especially with the single-thread fallback used when cross-origin isolation is unavailable. Keep the tab open, close other heavy tabs, or use a desktop encoder for very large files.
The original may already use efficient settings, or the selected quality and resolution may preserve more data than the source bitrate. Nothing replaces your original. Try a lower resolution, the Smaller file preset, WebM output, or Remove audio, then compress again and compare the exact sizes.