Where the upload zone lives
Two places, depending on whether your project has files already.
An empty project
When the project is empty, the services and files panel shows a single 150 × 150 dashed-border upload zone with Upload or drag file to start . Click it or drag a PDF onto it.
A project that already has files
Each service in the panel has its own inline Add more files zone at the bottom. The same controls — drag a PDF in, or click to open the file picker. While you're dragging, the label changes to Drop files here.
Uploading by drag-and-drop
- 1
Locate one or more PDFs in your file explorer.
- 2
Drag them onto the upload zone. The zone highlights while you're holding the files over it.
- 3
Drop. Each file uploads in turn — you'll see a progress indicator on the file card while it processes.
Uploading via the file picker
- 1
Click the upload zone . Your operating system's file picker opens.
- 2
Select one or more
.pdffiles. The picker only shows PDFs because the upload zone filters by file type. - 3
Confirm — the files upload and appear in the panel.
You can select multiple files at once in the picker (Ctrl-click or Shift-click on Windows, ⌘-click on macOS) — ZeroCount uploads them in parallel.
What happens during upload
Each file goes through three steps before it's ready:
- Transfer — the file is sent to ZeroCount's storage.
- Render — page thumbnails are generated.
- Pre-detection — ZeroCount runs a quick OCR pass to suggest AOIs and the legend, so Stage 1 isn't starting from a blank canvas.
A spinner sits on the file card during all three. When it disappears, the file is ready to open.
What if I dropped a non-PDF?
Non-PDFs are silently rejected — no error, no toast. If you dropped six files and only four turned up, the missing two were probably DWGs or images. Export them to PDF and try again. See Supported file types.
Where the file lands
If you upload into an empty project, ZeroCount creates a default service to put the file in. Otherwise the file goes into whichever service's upload zone you dropped it on. You can move files between services afterwards — see Moving files between services.