How to lock a folder on mac with password without disk utility?

While you mentioned "without Disk Utility," creating a password-protected disk image is the most straightforward free method to lock a folder on Mac. This typically involves Disk Utility, but you can also do it via Terminal, which is free and built-in.

Here's how to lock a folder on Mac via Terminal:

1. Open Terminal (Applications > Utilities > Terminal)
2. Create a sparse disk image:
   hdiutiil create -size 100m -fs HFS+J -volname "PrivateFolder" ~/Desktop/PrivateFolder.dmg
   Adjust -size 100m to your needs.
   This creates a disk image named PrivateFolder.dmg on your Desktop.
3. Convert the disk image to be password protected:
   You can create a new encrypted image with:
   hdiutiil create -encryption -size 100m -volname "PrivateFolder" -fs HFS+J ~/Desktop/PrivateFolder.dmg
   During this process, you'll be prompted to set a password.

Note: About how to lock a folder on Mac. The above commands create a new encrypted disk image. You can then mount it and add your private files inside. When done, eject it; the files are protected.