Chip Memory Map Visualizer
Where UID, lock bytes, capability container, user memory and configuration pages live on each chip — drawn to scale from the datasheet.
MIFARE Ultralight EV1 MF0UL11 (80 B / 20 × 4-byte pages)
Why memory maps matter
These maps show byte offsets and the role of each region. User-memory size does not include every byte on the chip, and it does not guarantee an equally large NDEF payload. MIFARE Classic sector trailers are interleaved with data: one 16-byte trailer per sector. On a 1K part, trailers occupy 256 bytes (25%); the manufacturer block leaves 752 data bytes. On a 4K part, trailers occupy 640 bytes, leaving 3440 data bytes after the manufacturer block. Formatting and access rules can reduce usable application space further. The ICODE SLIX view covers its user area only, and the T5577 view covers page 0 only. Consult the linked chip document before writing configuration or lock bits.
FAQ
Are these layouts exact to the datasheet?
The maps are reference layouts for the named variants and scopes. Addresses and region sizes are shown explicitly; verify the exact part and datasheet revision before writing.
Why don't you cover MIFARE DESFire or NTAG 424 DNA here?
Those are file-based, not page-based — the addressable unit is an application + file, not fixed pages. A page-grid visual would misrepresent them; use the datasheet's file structure diagram instead.
What are lock bytes and sector trailers?
Lock bytes flip an individual page or range from writable to read-only (permanent on most chips). Sector trailers on MIFARE Classic hold two 6-byte keys and 4 access-condition bytes — one trailer per sector, non-negotiable.
Can I write to configuration pages?
Yes, but carefully. They control password protection, mirror behaviour, and access permissions; a bad write can permanently lock a tag.