Citadel

Keep what's yours, yours.

Lock any folder or file on your computer behind one PIN. What you lock is encrypted, not just hidden. Free.

Choosing your Nomad PIN: six boxes, four digits typed, and Set PIN.

Locked means encrypted.

Locked files are encrypted, so they stay unreadable even if someone copies them off the computer.

What you can lock.

  • Any folder or file

    Pick as many as you like. They are encrypted on the spot, and open again with your PIN.

  • Any appPremium

    Put an app behind your PIN, so the people around you cannot open your mail or your browser when you step away.

  • Drives you plug inPremium

    Lock USB sticks and external drives too, with the same PIN.

Three steps. One PIN for everything.

  1. Choose what to lock

    Any folder or file on your computer. Pick as many as you like.

  2. Set your PIN

    One six-digit PIN for everything you lock. Forget it, and a code to your email sets a new one.

  3. It stays locked

    Locked files are encrypted, so they stay unreadable even if someone copies them off the computer.

Citadel and Citadel Premium.

Your files stay yours whether you pay or not: no plan ever decides whether you can open what you locked.

Yearly is two months free

Citadel

Lock folders and files, encrypted.

Free

Download Citadel
  • Lock any folder or file
  • Real encryption, not hiding
  • One PIN for everything
  • Reset a forgotten PIN by email

Citadel Premium

Lock your apps too. And unlock with a glance.

$19 a year

$1.58 a month, billed yearly. Two months free.

Buy Citadel Premium
  • Everything in Citadel, plus
  • Lock any app behind your PIN
  • Unlock with Windows Hello or Touch ID
  • Auto-lock when you step away or your computer sleeps
  • Lock USB and external drives

Included in MeridianOS

Built into your desk.

Every MeridianOS desk can lock folders and files with Citadel, and Meridian Pro and Ultra include Citadel Premium on the desk. The Citadel app on its own, for a computer outside MeridianOS, has its own subscription.

Frequently asked questions.

What if I forget my PIN?

A code sent to your email sets a new one.

What happens to my files if I stop paying for Premium?

Nothing. A plan never decides whether you can open what you locked. Without Premium, app locking and the conveniences switch off; your locked folders and files stay locked, and open with your PIN as before.

Is locking an app the same as encrypting it?

No. Locking an app keeps the people around you from opening it when you step away. Folders and files are different: what you lock is encrypted, so it stays unreadable even if someone copies it off the computer.

Do I need Citadel if I have MeridianOS?

Not on your desk: every MeridianOS desk can lock folders and files, and Meridian Pro and Ultra include Citadel Premium there. The Citadel app on its own is for a computer outside MeridianOS, with its own subscription.