Troubleshooting video uploads

Most upload problems come down to a handful of causes. Work through these.

The file is rejected before uploading

The upload check enforces four limits:

• Format — MP4, MOV, or WebM only. Export from your editor accordingly; container renames don't count.
• Size — up to 4 GB.
• Duration — up to 30 minutes.
• Bitrate — up to 200 Mbps. ProRes and other editing/master formats blow way past this; a delivery export at 10–30 Mbps looks identical on the web and uploads far faster.

If your file busts a limit, re-export. For FOOH spots, an H.264 MP4 is the safe bet.

The upload is slow or seems stuck

Files over 200 MB are compressed in your browser before uploading — you'll see "Compressing video..." first, which can take a moment for long clips. Uploads resume automatically if your connection drops mid-transfer, so a brief blip won't lose your progress — just keep the tab open, since a laptop that goes to sleep still pauses the upload.

Dropping several files at once uploads them one after another, and the dropzone counts them off ("Uploading 2 of 4 — 37%"). A few GB of video takes a while — as long as the percentage is moving, it's working.

Uploaded, but no thumbnail or playback yet

After upload, Cloudflare processes the video for streaming. The thumbnail and player usually appear within a minute or two. If processing fails — for example because the file's bitrate is over the 200 Mbps limit — the editor shows the reason; replace the video with a re-export (H.264, 10–30 Mbps). If an entry still shows no video after several minutes with no error, reload the editor — and if it's genuinely stuck, delete the video and upload again.

The thumbnail is wrong or ugly

The thumbnail is grabbed automatically from early in the video. If your clip opens on black, that's what you'll get — set a custom thumbnail in the work editor instead.

Still stuck?

Send us a message via the form at the bottom of the support page with the entry title and what you tried — we'll take a look.