The Pages file (.pages)

A .pages file is a document from Pages, Apple's word processor. Pages is free on every Mac, iPhone and iPad, and also runs in a browser as Pages for iCloud. Apple introduced it in January 2005 as part of iWork '05, and rebuilt it as Pages 5.0 in 2013, when Pages, Numbers and Keynote moved to the shared storage format they still use.

A Pages document is one of two kinds. In a word-processing document, text flows from one page to the next and new pages appear automatically, as in Word. In a page layout document, you place text boxes, images and other objects freely on each page, for flyers, posters and newsletters. You can convert between the two in the File menu.

Three things a Pages file is not:

• Not a Word file. Word, Google Docs and most other programs can't open .pages files. To share with them, export to DOCX or PDF.
• Not an open format. Apple publishes no specification; what's known about the inside comes from reverse engineering.
• Not always a single file. A Pages document can also be saved as a package: a folder that a Mac shows as one file. Packages break easily when emailed or uploaded through a browser.

Since 2013, Pages documents are made of IWA (iWork Archive) files, shared with Numbers and Keynote. The structure has been worked out by the SheetJS project and other reverse engineers:

• Each .iwa file is Snappy-compressed in chunks: a 00 byte, a 3-byte length, then Snappy data.
• Inside are Protocol Buffers messages. The message definitions are compiled into the apps; reverse engineers extract them from the app binaries. Some definitions are used only by Pages, others are shared by all three apps.
• Objects point to each other by number. Index/Metadata.iwa maps the document's components to the files that hold them.
• Media stays as it is. Pictures and other media sit in the Data folder of the ZIP as ordinary files.

Pages saves a single file by default. On a Mac you can switch to a package, or back, with File, Advanced, Change File Type. Pages may suggest a package for documents over 500 MB on disks that don't use APFS.

Pages is a good format while everyone involved uses Apple devices. As soon as someone on Windows or Android needs the document, send a DOCX for editing or a PDF for reading.

1. 1Use Pages for iCloud. Go to iCloud.com in a browser on Windows or any computer, sign in with an Apple Account (creating one is free), open Pages and upload the file. You can read and edit it there, then download a copy as Pages, PDF, Word or EPUB.
2. 2Ask the sender to export it. In Pages: File, Export To, Word (or PDF). This is the most reliable route, because the person exporting can check the result.
3. 3Look at the preview, as a last resort. Rename a copy to .zip, open it, and open preview.jpg. It's only a small picture of the first page, not the text.

• On iPhone and iPad: tap the Share button, then Export and Send, and pick a format.
• In Pages for iCloud: download a copy as Pages, PDF, Word or EPUB.
• From Word to Pages: Pages opens DOCX, RTF and plain-text files; save them as Pages documents to keep editing in Pages.
• What can change in Word: Pages and Word lay out text with different engines and fonts, so line and page breaks can move. Page layout documents, with freely placed objects, change the most. Check the DOCX before sending it.

In Pages on a Mac, File, Set Password encrypts a document; on a Mac with Touch ID you can also open it with your fingerprint. A protected document's contents can't be read without the password, by Pages or anything else.

• There's no recovery. Apple says there's no way to recover the password if you forget it.
• Exports keep the password. A protected document exported to PDF, Word or Pages '09 is protected with the same password, unless you change or remove it in the export dialog.
• The hint isn't secret. iWork keeps the password hint unencrypted. In our password-protected Numbers sample, it sits in plain text in its own entry of the ZIP, so never put the password in the hint.

• Word or Google Docs can't open it. Neither reads .pages files. Convert it through Pages or iCloud.com first.
• The attachment arrived as a folder, a ZIP or a broken file. The document was saved as a package. Ask the sender to choose File, Advanced, Change File Type, Single File, and send it again.
• Windows shows an unknown file type. Windows has no program for .pages. Use iCloud.com, or ask for a DOCX or PDF.
• Fonts look different. Pages may warn about missing fonts or layout changes when a document uses fonts your device doesn't have. Install the fonts, replace them, or ask for a PDF.
• The file is dimmed and won't open. Apple says a dimmed file isn't in a format Pages can open. Update Pages, and check the file really is a Pages document.

Pages has no macro language inside documents, so a .pages file can't carry VBA-style macros the way Word files can. A few things are still worth knowing:

• Preview images show content. The thumbnails inside an unencrypted document are pictures of its first page. Anyone who unzips the file can see them.
• Comments and author names travel with the file, as do earlier changes if change tracking was on.
• Links in the text can point anywhere. Check where they go before clicking.
• Parsing uploads on a server. A Pages file is a ZIP of compressed binary data, so a server that reads uploaded files inherits ZIP risks such as archive bombs. Limit file size and decompressed size.