What happens
One of these:
- The tool shows Stopped at 63% (or This job stopped) and says the browser’s video encoder gave up.
- The progress stops moving and nothing else happens.
- The whole tab reloads or goes blank — Chrome shows “Aw, Snap!”, Safari says the page was reloaded because a problem occurred.
Nothing was downloaded. If the tab reloaded, whatever you had set up in the tool is gone too; if the tool shows “Stopped at”, your settings are still there.
Why it happens
The video tools work inside your browser, so the whole job runs in the memory your browser is allowed to use — nothing is sent to a server to do it for you. A long or high-resolution video needs much more of that memory than a short one: the soundtrack is held while the video is rebuilt, and frames are drawn at full size. When the browser runs short, it stops the encoder or closes the tab. Less often, the graphics driver restarts part-way, which stops the encoder in the same way.
When a video looks too heavy for your device, the tool warns you before it starts with This video is heavy for this device. In Chrome or Edge on a computer with 8 GB of memory, that warning appears from about an hour of 1080p video, or half an hour of 4K. Firefox and Safari do not tell a page how much memory the device has, so the tools assume less and warn sooner: from about a quarter of an hour of 1080p, and for any 4K video. Phones and tablets give a browser tab much less memory, so the point comes sooner there too.
What to do
- Close other tabs and apps, reload the tool page and try again. If the tool shows Try again, that is the quickest way.
- Cut the video into parts with the Video Splitter, process each part, then join them with the Video Merger. The heavy-video warning has a button that takes you straight there.
- Make the video smaller first: a lower resolution with the Video Compressor makes the biggest difference.
- Use a computer if you were on a phone or tablet, and keep the tab in front while it works.
- Use an up-to-date Chrome or Edge. See which browsers work.
If it still stops
Press Copy details for support on the message, then send it to us from the contact page along with the length and resolution of the video. The details never include the video itself.