How to open .KEY files on iOS
To open .KEY files on iOS, open the .key file in Apple Keynote for iOS (if it is a Keynote presentation) or request an exported format if you cannot open it.
Step-by-step instructions
- Open the .key file in Apple Keynote for iOS (if it is a Keynote presentation) or request an exported format if you cannot open it.
Common issues
The .key file won’t open (wrong type of .key)
.key is most commonly a Keynote presentation, but it is also used for exported PGP/GnuPG keys in practice. If you try to open a PGP key file in a presentation app (or vice versa), it will fail or look like gibberish.
- Confirm what you received: was it meant to be a presentation (slides) or a cryptographic public key for encryption/verification?
- If it is a PGP/GnuPG key file, import it using your OpenPGP/GnuPG tool rather than opening it as a document.
- If it is a Keynote presentation and you are not on macOS/iOS, ask the sender to export it from Keynote to a widely readable format (such as PDF) for viewing.
Linux desktop shows an unexpected app for .key files
On Linux, file opening behavior depends on MIME type detection and extension associations, which are often managed through the shared-mime-info database. If the association is incorrect, double-click may open the wrong tool.
- Right-click the file and choose “Open With…” to select the correct application for this specific file.
- If it is a Keynote presentation but you lack a suitable viewer/editor, open it on macOS with Keynote or request an export (e.g., PDF) from the sender.
- If it is a PGP key export, use a GnuPG-compatible key management/import tool instead of a presentation app.
Someone sent me a .key but I only need to view it
Keynote presentations are best viewed in Keynote, but many recipients only need a read-only copy. Converting/exporting from Keynote avoids platform and compatibility issues.
- Ask the sender to open the file in Apple Keynote and export it to a viewer-friendly format (commonly PDF).
- If you need to present and not edit, request an exported format that preserves appearance closely.
- Keep the original .key if you may need to edit later in Keynote.
Security note
Do not import a .key file into your OpenPGP/GnuPG keyring unless you trust its source. Key files are used for identity and trust decisions; importing an attacker-provided key and trusting it can lead to verifying the wrong signatures or encrypting to the wrong person.