Help Center/Features/File Previews

File Previews

When you upload files to ZappFiles, we generate thumbnail previews so your recipients can see what they are downloading before they start. Photos, camera RAW files, videos, PSDs, PDFs, and Illustrator files all get a real preview. Everything else gets a file type icon.

Which image formats get a preview?

Thumbnail previews are generated for the common image formats:

  • JPEG and JPG
  • PNG
  • GIF
  • WebP
  • BMP
  • TIFF
  • HEIC and HEIF
  • AVIF
  • SVG

Camera RAW previews

RAW files from every major camera brand get a real thumbnail on the download page: Canon CR2 and CR3, Nikon NEF, Sony ARW, Fujifilm RAF, Olympus ORF, Panasonic RW2, Pentax PEF, Hasselblad 3FR, Phase One IIQ, and DNG. The preview is the JPEG your camera saved inside the file when you pressed the shutter, so it shows the frame as the camera rendered it, not a later edit. The RAW file itself travels exactly as shot.

Video previews

ZappFiles supports video previews for common formats like MP4, MOV, AVI, WEBM, and MKV. On the download page, recipients can click a video to stream the full file directly in their browser before deciding to download it. There is no length limit on the preview. Your recipient can watch the whole thing.

PSD, AI, EPS, and PDF previews

Photoshop files get a real preview on the download page, not a generic icon. So do Illustrator files, EPS artwork, and PDFs, which show their first page. Your client sees the work itself, so a folder of layered PSDs or a stack of proofs arrives looking like the work rather than a list of file names. Click one to open it in the larger view like any other image.

One exception: in your own upload view, before the transfer finishes, a PSD, RAW, or PDF is shown with its file type icon. Those thumbnails are drawn in your browser and it can only read standard web image formats. The rendered preview appears once the upload completes.

When do previews appear?

Previews for standard image formats are generated right in your browser when you select your files, so they show up almost instantly in the upload view. RAW, PSD, and PDF previews are rendered on our side once the upload completes. On the download page, previews may take a couple of minutes to become available after your upload finishes. This is normal, especially for larger uploads with many images or videos.

Preview quality

Thumbnails are small, compressed versions of your files used only for the preview. They do not affect the quality of the actual download. Your recipients always get the original, full-resolution file.

File type icons

Files that do not support visual previews are shown with a clear icon based on their extension. ZappFiles recognizes over 40 file types including FIG, DWG, ZIP, RAR, DOCX, PPT, MP3, WAV, and many more. Audio files are covered by icons rather than a player, so a WAV shows up as a WAV. Recipients always know what kind of files they are about to download.

Previewing before downloading

On the Classic and Grid appearances, recipients click an image to open it in a larger view, or click a video to stream it at full quality. On Reel the highlighted file is already the large view, so a video plays right there on the page. Either way, recipients can inspect the work before they commit to the download.