Why does my upload keep failing?

Most upload failures come down to file size or format, not a broken feature.

Most upload failures come down to file size or file type, not a broken feature. Here is what to check, in order.

Check the file size against the real limits

The limit depends on what you are uploading:

If your file is near one of these numbers, compress it or export a smaller version and try again.

Large or high-resolution photos usually still work

A common worry is that a very detailed image will be refused for its resolution. It will not be. If an image is wider or taller than 4000 pixels, or over 16 megapixels, it is resized down automatically rather than blocked. Files over 8 MB are recompressed the same way.

So a large camera photo or a big export from your rendering software generally goes through, just at a smaller size than the original. What still stops it is the file size limit above, so a 30 MB export needs compressing first.

Accepted file types

Project media in the builder: JPEG, PNG, GIF, WebP, BMP and TIFF, plus MP4 for video. SVG is the one format the picker offers on some screens and we refuse, because an SVG can carry scripts. Convert an SVG to PNG before uploading.

Project cover image: JPEG, PNG or WebP.

Publications: PDF.

If you are uploading something outside these lists, a CAD file, a RAW camera format, or a MOV or AVI video, that is the likely cause rather than a size problem.

Uploading photos from an iPhone

iPhones save photos as HEIC by default, and HEIC is not one of the accepted types above. If photos straight from your phone are refused, either export them as JPEG first, or open Settings, then Camera, then Formats on the phone and choose Most Compatible, so new photos are saved as JPEG.

If the error message is unhelpful, or just says "undefined"

  1. Confirm the file type is in the accepted list above.
  2. Confirm the file size is under the relevant limit above.
  3. Re-export or re-save the file. A fresh export sometimes fixes a file that looks fine locally but is subtly damaged.
  4. Hard reload the page (Ctrl+Shift+R, or Cmd+Shift+R on a Mac) and try again, in case the page was in a stale state.
  5. Try a different browser or device to rule out something local.

If it still fails after all of that, tell us what you were uploading and where, and we will check it from our end.

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