What's the difference between .one and .onepkg?

.one is a single section of a OneNote notebook. .onepkg is a whole notebook packaged together. mydocs.school delivers per-section .one files; OneNote's built-in export typically delivers a single .onepkg per notebook. Both open with OneNote on every modern platform.

Can I open a .one file without installing OneNote?

Not natively — the file format is OneNote-specific. The free OneNote app (Windows, Mac, iOS, Android, web) is the easiest path. The web app at onenote.live.com works with a free Microsoft account and doesn't need an install.

Will my ink, images and embedded files come through?

Yes. The .one binary contains the full page structure: text, ink layers, embedded images, attached files, and the page hierarchy. Opening a .one in OneNote gives you a faithful reconstruction of the original section.

Why does Send as PDF lose stuff?

PDF is a flat format — it doesn't understand pages within sections, links between pages, ink layers, or attached files. Sending a notebook as PDF flattens everything into one document. Keep the .one files as your authoritative archive and use PDF only for quick sharing.

File types · OneNote

The .one file survival guide.

The raw OneNote sections you exported are .one files. They're the authoritative archive of your work. Here's how to open them on whatever computer you have today.

Windows

Open OneNote (the modern Windows app, not OneNote 2016 unless that's all you have). Create a new personal notebook on your own Microsoft account. Click File > Open, navigate to the .one file, click Open. The section appears inside your personal notebook.

For .onepkg files, use File > Open the same way; OneNote will unpack the entire notebook into your account.

Mac

Open OneNote for Mac. Sign in with a personal Microsoft account. Drag the .one file into the OneNote window, or use File > Open Notebook. The Mac client handles the same file formats as the Windows one.

Web (no install)

Open onenote.live.com in a browser. Sign in with a free Microsoft account (use a personal email, not your school one — that one's closed). Create a new notebook. Use File > Open and upload your .one file — it appears as a section.

The web app is the right answer if you don't have OneNote installed and don't want to install it. The free tier's storage is enough for a typical leaver's archive.

iOS and Android

The mobile OneNote apps don't directly open .one files from the device's file picker — Microsoft expects mobile content to come down via sync. The workaround: upload the .one to your OneDrive (personal account), then open it in OneNote on mobile.

Easier path: use the web app from your phone's browser, or do the import from a laptop and let it sync to your phone after.

Long-term archive recommendation

Keep the .one files as your primary archive — they preserve everything. As a secondary archive, export each notebook to PDF once you've imported it. The PDFs are easier to skim later without OneNote installed, and they survive Microsoft format changes.

For the deeper detail on why class notebooks export the way they do, see the class notebooks guide.

Common questions

What's the difference between .one and .onepkg?: .one is a single section of a OneNote notebook. .onepkg is a whole notebook packaged together. mydocs.school delivers per-section .one files; OneNote's built-in export typically delivers a single .onepkg per notebook. Both open with OneNote on every modern platform.
Can I open a .one file without installing OneNote?: Not natively — the file format is OneNote-specific. The free OneNote app (Windows, Mac, iOS, Android, web) is the easiest path. The web app at onenote.live.com works with a free Microsoft account and doesn't need an install.
Will my ink, images and embedded files come through?: Yes. The .one binary contains the full page structure: text, ink layers, embedded images, attached files, and the page hierarchy. Opening a .one in OneNote gives you a faithful reconstruction of the original section.
Why does Send as PDF lose stuff?: PDF is a flat format — it doesn't understand pages within sections, links between pages, ink layers, or attached files. Sending a notebook as PDF flattens everything into one document. Keep the .one files as your authoritative archive and use PDF only for quick sharing.