Yes — Kopitiam runs in your browser and is ad-funded: no export paywall, no watermark, no sign-up.

Do my files get uploaded?

No. Page numbers are added entirely in your browser; your PDF never leaves your device.

Can I start numbering from a page other than the first?

Yes. Skip the first page (for a cover) and set the starting number, so the numbering matches your document.

Number every page — free, in your browser. Your file never leaves your device.

or click to choose a file. Everything stays on your device.