Yes, IPSW files are safe to use as long as they are downloaded from trusted sources like ipsw.io.

What is an IPSW file?

An IPSW file is a firmware update file used by Apple devices, including iPhones, iPads, and iPods, for restoring or updating their operating system.

How do I install an IPSW file?

You can install an IPSW file using iTunes or Finder (on macOS Catalina and later). Download the correct IPSW file, connect your device, and use the 'Restore' option while holding Shift (Windows) or Option (Mac) to select the IPSW file.

Can I downgrade my iPhone using IPSW?

You can downgrade your iPhone using an IPSW file only if Apple is still signing the previous iOS version. Unsigned IPSWs cannot be restored via iTunes.

How do I check if an IPSW file is signed?

You can check the signing status of an IPSW file using ipsw.io, where we provide real-time updates on which versions are currently signed by Apple.

Can I use IPSW to jailbreak my device?

Some jailbreak tools require specific IPSW files, but installing an IPSW alone does not jailbreak a device. You need additional tools such as checkra1n or unc0ver.

iPhone 11 Pro Max

Firmware Build 21C66

Choose a

Product

Choose a

Platform

Choose a

Version

Click on

Download

Download iPhone 11 Pro Max IPSW — Build 21C66

Identifier: iPhone12,5 · All firmware links redirect directly to Apple's official servers.

✗ This firmware is not signed. This means you cannot restore to it in iTunes.

Release Date:	1st January 1970
Upload Date:	1st January 1970
Filename:	iPhone12,3,iPhone12,5_17.2.1_21C66_Restore.ipsw
Filesize:	6.95 GB
SHA256sum:	`e135107807517e6f60202a26806cf7ea7ee625b1bbbb59d8b966414af0ff92a5`
MD5sum:	`c4f1e21c276108c510c32be8291d04cb`
SHA1sum:	`6b0be6e23dedcf9c3f43b983a99102a383fed499`
Identifier:	iPhone12,5

🔒 Secure download – redirects to Apple.com

Download (6.95 GB)

How to Install?

Before installing make sure to follow these steps given below

Step 1

Backup your data

Make sure you have backed up your device using iCloud or iTunes on your PC or Mac. Otherwise, you may lose your data.

Step 2

Connect your device

You can connect your device using a Lightning or USB-C cable to your PC or Mac.

Step 3

Turn off Find My

On your device, go to Settings - [your name] Find My - Find My iPhone/iPad, then turn off the Find My iPhone/iPad.

Step 4

Install .ipsw file

In iTunes or Finder (Mac), hold down the Shift key (or the Options key on a Mac) and click on Restore iPhone... button.

Step 5

Restore your backup

After iTunes has installed the .ipsw file on your device, follow the on-screen instructions to restore your data.

Ad Blocker Detected!

Firmware Build 21C66

Download iPhone 11 Pro Max IPSW — Build 21C66

Connecting...

5 seconds

How to Install?

Step 1

Backup your data

Step 2

Connect your device

Step 3

Turn off Find My

Step 4

Install .ipsw file

Step 5

Restore your backup