A PlayStation 4 keeps every game, save, and patch on one 2.5-inch drive. When that drive fills up or starts clicking, an SSD is the cheapest way to keep the console alive without losing the library.
This guide explains how the console protects its data, what to check before the copy, and how to clone the drive so the PS4 still recognises it.
Every PS4 model stores its data on a single 2.5-inch SATA drive, so the console treats a replacement exactly like the original unit. A full clone keeps the encrypted layout intact and lets the console read the copy.

Shut the console down completely instead of leaving it in rest mode before you remove the drive. Rest mode keeps the disk powered, and a copy that starts mid-write can miss blocks.

Do not initialise or format the new SSD in Windows. Any partition Windows creates is overwritten by the clone, and a formatted drive can hide the capacity the console expects.
Qiling Disk Master copies a disk block by block, so the console partitions and their encrypted contents survive the move. Run it on a Windows PC with both drives attached.
Step 1. Open Qiling Disk Master, choose Clone, and then select Disk Clone.

Step 2. Select the PS4 drive as the source and click Next.

Step 3. Select the new SSD as the destination and confirm that its data will be replaced.

Step 4. Review the partition layout, keep every console partition, and tick Sector by sector clone.

Step 5. Click Proceed, wait for the copy to finish, then shut the PC down before you unplug the adapter.

If the console shows a storage error, the copy was incomplete. Reconnect the original drive and repeat the clone with the sector-by-sector option enabled.
Yes. A full clone copies the used partitions, and the console accepts a drive larger than the original.
Usually not when the clone is exact. Keep the update file on a USB stick in case the console asks for it.
The copy may have started in rest mode, or the adapter dropped mid-task. Redo the clone from a full shutdown.
No. The data stays encrypted with the key held in the console, which is why the copy works only in that unit.
No. The key belongs to the original console, so a second console cannot decrypt the copy.
Before you swap drives, create a full disk image. Qiling Disk Master can write an image of the source drive that you restore later.
Step 1. Open Qiling Disk Master and select System Backup, then add the console partitions to the task.

Step 2. Save the image to a drive other than the target disk and start the backup.

Step 3. Click Proceed to start the system backup and wait patiently until it finishes. You can also tick Shut down the computer when the operation is completed to power off automatically.

Step 4. If the console will not start on the copy, restore the image to the original drive and try again.

A PS4 SSD upgrade is a raw disk copy, not a Windows migration. Shut the console down fully, update it first, and keep the original drive as a rollback. Attach both drives to a PC through a SATA adapter, clone every console partition with the sector-by-sector option, then fit the SSD and confirm the reported capacity. Test one game and its save before you delete anything from the old drive.
For more on copying console and removable storage, see How to Clone a Steam Deck SSD, How to Clone a Bootable USB Drive to Another USB, How Long Does a Disk Clone Take, and How to Clone a Failing SSD Before It Dies.