Merge PDFs without uploading them
Drop several PDFs in, drag them into the order you want, download the result. The files are read from your disk and joined in the browser tab.
What “without uploading” actually means
Every mainstream merge tool sends your documents to a server: that is how a website can process a file at all. The upload happens before you see a progress bar, usually within a second of dropping the file.
Slate is different in kind, not degree. The PDFs are parsed by JavaScript running in your tab. Open the network panel of your browser while merging and you will see no request carrying the file. Turn off Wi-Fi after the page loads and the merge still completes.
How to merge, step by step
Drop two or more PDFs onto the tool, or click to browse. Each file appears as a row with its page count. Use the arrows to move a file up or down — the list order is the page order in the finished document.
Press Merge. The result is a single PDF with the pages joined end to end, keeping each page’s original size and orientation. A four-page contract and a two-page schedule become one six-page file.
When merging goes wrong
Password-protected PDFs cannot be merged without the password, and the tool will say so rather than producing a corrupted file. Very large scans can exhaust browser memory — the practical ceiling for a single file here is 100 MB.
Is there a page limit?+
No page limit. Each file must be under 100 MB, and you can add as many files as you like.
Does merging reduce quality?+
No. Pages are copied as they are, not re-rendered, so text stays selectable and image quality is unchanged.
Do I need an account?+
Yes — the service is subscription-based, with the first week free. No card details are taken to start.
Files are processed in the browser tab and are never uploaded. Slate is not legal advice or a case management system.