Open Password-Protected ZIP on iPhone — AES-256 in Safari
Encrypted ZIP files on iPhone are especially tricky — iOS's built-in ZIP support (in the Files app, "Expand" option) handles unencrypted ZIPs only. If you try to expand an AES-256 encrypted ZIP through Files, you get an error with no useful message. Third-party apps in the App Store can open encrypted ZIPs, but most are ad-supported or require subscriptions.
FastZip handles both ZipCrypto and AES-256 encrypted ZIP files in Safari on iPhone, with no app download required.
Why encrypted ZIPs land on your iPhone:
- Bank statements — Banks in Japan, India, Singapore, South Korea, and other markets routinely protect PDF statements in AES-256 encrypted ZIP files. The password is typically your account number or date of birth in a specific format.
- Corporate documents — HR departments and legal teams email sensitive documents (offer letters, contracts, NDAs) as password-protected ZIPs to prevent interception.
- Insurance and government documents — Tax documents, insurance certificates, and government forms from some countries arrive as encrypted ZIP attachments.
- Software licenses — License files for desktop software sometimes arrive in a password-protected ZIP.
How to find the password — If you received the encrypted ZIP by email, the password was likely communicated separately (by SMS, a phone call, or in a previous email). Banks commonly use a standard password format (e.g., date of birth as DDMMYYYY). Check any accompanying message or email thread for the password.
Format & Feature Reference
| Method on iPhone | AES-256 ZIP | ZipCrypto ZIP | App Install |
|---|---|---|---|
| FastZip (Safari) | Yes | Yes | No |
| Files app (iOS "Expand") | No | No | No (built-in) |
| iZip (App Store) | Yes | Yes | Yes |
| RAR for iOS | Yes | Yes | Yes |
| WinZip for iOS | Yes | Yes | Yes (subscription) |
Opening Bank Statement ZIPs on iPhone
Many Asian banks (common in Japan, India, Singapore, Indonesia, and South Korea) send monthly statements as AES-256 encrypted PDF-in-ZIP files. The password is typically fixed: your account number, date of birth, or a combination specified in the bank's instructions.
To open on iPhone: save the ZIP from Mail to Files, then open Safari and navigate to fastzip.io. Tap the drop zone, select the ZIP from Files, and when prompted for a password, enter your bank's standard password format. The PDF inside will download to your Files > Downloads and can be opened in Preview or any PDF reader.
Opening Encrypted ZIPs Received in Gmail on iPhone
In Gmail on iPhone, tap the ZIP attachment. If Gmail can preview it, you'll see a generic file icon — tap the share icon (box with arrow) and choose "Save to Files". Then open Safari, go to fastzip.io, select the file from Files, and extract.
If Gmail opens the attachment in a preview (showing a "No preview available" message), look for a download button in the top-right corner of Gmail's in-app viewer. Download to Files, then open in FastZip.