By RFID MFG Editorial Team · Updated October 25, 2026 · 4 min read
Which chip family fits your project?
| Project | Starting point | Decision before ordering |
|---|---|---|
| Open a web link with a phone | NTAG213 / 215 / 216 | Choose capacity from the encoded record and test the intended phone action. |
| Replenish an installed Classic system | The approved MIFARE Classic EV1 variant | Match the credential layout, issuing process and installed reader support. |
| Use an application with defined access rights | A system-supported MIFARE DESFire variant | Specify applications, files, authentication and personalization responsibilities. |
| Issue a limited-use ticket | The exact MIFARE Ultralight variant supported by the platform | Match the ticket format, authentication requirements and issuing equipment. |
| Tag items in an ISO/IEC 15693 installation | The approved ICODE variant | Match the reader commands, data layout and finished label construction. |
NTAG213/215/216 are NFC Forum Type 2 chips. Classic EV1 uses sectors and blocks with CRYPTO1 authentication. DESFire EV3 uses applications and files and supports AES-128 among its cryptographic options. These capabilities do not make the parts interchangeable.
For phone projects, the MIFARE vs NTAG guide explains NDEF and device support. For an installed credential system, use the Classic replacement and DESFire migration guide. Keep the approved credential specification when replenishing a working installation; treat a change of chip family as a system decision.
Record the exact variant and usable memory
Ask for the part reference and the memory area available to your application. Total chip memory, user memory and space for an encoded record are different quantities. Configuration, access settings and record formatting can use space that is not available for your own data.
- NTAG213/215/216: user memory is 144, 504 and 888 bytes respectively. Use the NTAG capacity and encoding checklist to check the actual record.
- Classic and DESFire: specify the approved part and required sector layout or application/file allocation. Do not compare nominal memory sizes as if their data structures were the same.
- Ultralight: NXP lists distinct Ultralight products, including EV1, C and AES. Memory and authentication capabilities depend on the variant; “Ultralight” is incomplete.
- ICODE: the SLIX data sheet specifies 1024 bits of total EEPROM and 112 bytes of user memory. The SLIX2 data sheet specifies 316 bytes for user data, with a separate counter block. Bits and bytes must not be substituted for each other.
If data retention, repeated writing or temperature matters, include the expected use and ask for the relevant part's rated conditions. A chip rating does not establish the service life of a finished card, antenna, print or adhesive.
Turn a chip choice into a testable sample
Define what success looks like before ordering a production batch. The sample should represent the intended chip, antenna, material and encoded configuration.
- Identify the setup. Record the reader or phone models, issuing software and application task.
- Define the data. Provide a fictional example of the required fields, shared or individual records, and their relationship to printed numbers or QR codes.
- Assign preparation. Agree who writes, personalizes and issues the cards, and which write permissions apply at delivery.
- Run the task. Complete issuance and the intended use on the sample. A detected chip identifier alone is not acceptance.
- Retain the result. Keep the accepted specification and test record with the quote and production approval.
Security also depends on the application, key management and reader verification. A stronger chip algorithm or a locked public link is not, by itself, proof of a secure installation or an authentic product. Describe the requirement and responsible system provider; do not put production keys or live cardholder records in a general inquiry.
Prepare a quote for the finished card
For branded credentials, start with custom printed RFID cards. For a property's lock and front-desk workflow, start with hotel key cards. Include quantity, destination, needed date, artwork, the approved chip if known and encoding responsibilities. Unknown technical details can remain open for confirmation.
The existing forms provide editable project checklists. Compare written quotes for the same finished construction, data preparation and delivery scope, including sample costs, minimum quantity and timing.
Related reading
- Classic replacement and DESFire migration
- Phone interaction or reader credentials
- NTAG capacity and encoding checklist
- RFID card buying guide
Frequently asked questions
Is DESFire a different brand from MIFARE?
DESFire is part of the MIFARE portfolio, alongside other families such as Classic and Ultralight. Use the exact family, generation and part reference when specifying a credential.
Does the same 13.56 MHz frequency mean chips can be exchanged?
No. The reader, commands, data structure, application and issuing process must support the proposed part. Use the approved specification and test the complete workflow.
Does ICODE SLIX have 1 KB of user memory?
No. Its data sheet specifies 1024 bits of total EEPROM, including 112 bytes of user memory. SLIX2 has a different layout and 316 bytes for user data; identify the exact variant.
Which chip is the most secure?
There is no useful universal ranking for a finished installation. Specify the authentication, permissions and application requirements, then evaluate a supported chip together with issuance, key management and reader verification.