Systemic Studios
Can NFC tags be locked?
Yes. Many tags can be permanently locked so they become read-only. NFC Ninja Pro can lock NTAG21x tags after you confirm and type LOCK.
How to Password Protect or Lock an NFC Tag
Password or permanent lock: which one?
| Write password | Permanent lock | |
|---|---|---|
| Phones can still read it | Yes, unless you turn on read protection | Yes |
| You can change it later | Yes, with the password | No, never |
| Best for | Tags you may update, such as menus or specials | Finished tags that won't change, such as a review link |
| Needs | NTAG21x tags | NTAG21x tags |
Why lock a tag at all
An unprotected tag in a public place can be rewritten by anyone with an NFC app, which can send your customers somewhere you didn't choose. Protecting the tag keeps your link yours.
Add a write password
- Write and check your tag first.
- Open tag security in NFC Ninja Pro (Tag Security Manager on Android).
- Choose to set a password and enter one you will remember. Advanced options include PACK, read protection and a limit on failed attempts.
- Hold the tag to your phone.
- If you choose, save it securely on your phone. To change or remove the password later, you need the current one.
Permanently lock a tag
- Make sure the content is final. A permanent lock cannot be undone.
- Open tag security in NFC Ninja Pro (Tag Security Manager on Android) and choose Permanent lock.
- Confirm you understand it can't be undone and type LOCK. NFC Ninja reads the tag again right before locking.
- Hold the tag to your phone until it finishes.
NFC Ninja never locks a tag automatically.
Make it on your phone now with NFC Ninja. App Store · Google Play
Check your tag type first
Password and lock need NTAG21x tags. Read the tag with NFC Ninja to see its type and whether it can be written before you buy a batch.
What a lock does not do
A lock stops changes. It does not hide what is on the tag: anyone who taps it can still read the link, so never put private information on a public tag.
NFC NINJA PRO
Design. Deploy. Protect.
Keep your link yours
- Tag security (Tag Security Manager on Android): set, change or remove a write password (changes need the current password), with options for PACK, read protection and a failed-attempt limit. Save it securely on your phone if you choose.
- Permanent lock: make a finished tag read-only. You type LOCK to confirm, and the tag is read again right before locking.
- Tag Doctor: a plain-language reading of a tag so you know what you are protecting.
- Works with NTAG21x tags.
Pro is a one-time upgrade inside the NFC Ninja app, no subscription. Reading and writing tags work without Pro.
Protect your tags today
Add a password or lock a finished tag, so the link your customers tap stays yours.
Discover · Create · Tap
AVAILABLE ON IPHONE AND ANDROID
Set up your first tag with NFC Ninja
Pick an idea, build the tag in a few taps, write it, and see it verified. No account needed.
Frequently asked
questions
Can I unlock a permanently locked NFC tag?
No. A permanent lock cannot be undone. Use a write password instead if you may need to change the tag.
Can people still read a locked or password-protected tag?
Yes. A password and a lock stop changes, not reading, unless you turn on the optional read protection.
What tags support passwords and locking in NFC Ninja?
NTAG21x tags. Read your tag in NFC Ninja to check its type first.
Where is my tag password kept?
If you choose, NFC Ninja saves it securely on your phone.