This guide covers the core functionalities of the MIFARE Classic Tool (MCT) version 2.3.1, an Android application for interacting with MIFARE Classic RFID tags (1k, 4k, etc.). ⚠️ Important Disclaimer
This tool is for educational purposes and authorized security testing only. MIFARE Classic cards are considered insecure. Use on your own cards to understand NFC technology. 1. Prerequisites An NFC-enabled Android phone.
MIFARE Classic Tool 2.3.1 APK (available on F-Droid or GitHub). A MIFARE Classic tag (e.g., key fob, access card). 2. Core Functions Guide A. Read Tag (Basic) Open the app and select Read Tag.
Select a Key File (standard std.keys is usually sufficient for testing default keys). Place the tag on the back of your phone.
Result: The app will attempt to authenticate sectors and display the hex data. If successful, you will see key A/B and sector data. B. Write Tag Select Write Tag from the main menu.
Choose the Key File and Dump File (previously saved data) you want to write. Choose which sectors to write to. Place the tag on the phone.
Caution: Incorrectly writing to Sector 0 (Manufacturer Block) can permanently break the card (make it "bricked"). C. Clone Tool Select Clone Tool.
Read Tag (UID): Scan the source card to get its UID (Unique ID) and data.
Write to New Card: Place a "magic" (writeable) card on the phone to clone the UID and data. D. Key Management (Key File Generator) Select Edit/Create Keys. Here you can manage known keys (
) or create a new file with potential keys to brute-force a tag. 3. Troubleshooting
"No Tag Found": NFC is off, or the phone is positioned incorrectly (try moving it around the back of the phone).
"Authentication Failed": The keys in your key file do not match the keys on the tag.
Tag Not Supported: The tag is likely not a MIFARE Classic (e.g., it might be MIFARE DESFire or Ultralight). 4. Tips for Success
Use a "Magic" Tag (UID-changeable Gen1/Gen2 cards) if you need to clone the UID.
Version 2.3.1 includes features to "brute force" missing keys if you know some of the keys on the card.
To give you a better guide, what are you trying to do with the tool? Clone a card? Read data? Change a card's ID? Also, do you know if the tag is a MIFARE Classic 1K or 4K?
MIFARE Classic Tool (MCT) version 2.3.1 is an open-source Android application designed for low-level interaction with MIFARE Classic RFID tags. Released around October 2020, this version serves as a stable point in the tool's history for reading, writing, and analyzing tags using a device's built-in NFC controller. Core Features of MCT 2.3.1
The tool is built for users with basic technical knowledge of MIFARE Classic technology. Its primary capabilities include:
Reading & Analysis: Users can read data from MIFARE Classic 1K or 4K tags and display it in highlighted hex or ASCII formats.
Key Management: The app uses a dictionary-attack approach. Users can create and edit key files (dictionaries) to authenticate against sectors; version 2.3.1 includes standard and extended-std key files containing common default keys.
Cloning & Writing: It allows for block-wise writing and full tag cloning (writing a "dump" of one tag to another). Specialized Tools:
Tag Formatting: Reverts tags to their factory delivery state. mifare classic tool 2.3.1
Manufacturer Block Writing: Can write to "Block 0" of special "magic" tags (UID changeable tags).
Access Condition Decoder: Decodes and displays the complex access bits of each sector as a readable table.
Value Block Support: Decodes, encodes, and manipulates MIFARE Classic value blocks (often used for credit/counters). Technical Requirements
To use MCT 2.3.1, specific hardware and software conditions must be met: Operating System: Requires Android 4.3 or newer.
Hardware Support: The phone's NFC controller must support the MIFARE Classic protocol. Many modern devices (like some Google Pixel or newer Samsung models) do not support this protocol despite having NFC.
Input Format: All data input and output is in hexadecimal; there is no simplified "point-and-click" interface for saving custom URLs or text. Key Limitations
No Cracking: MCT cannot crack unknown keys directly on the phone. Keys must be known or found in the dictionary. Tools like Proxmark3 are typically used for initial key extraction.
No Brute-Force: The protocol is too slow to support brute-forcing keys through the app.
Data Risks: Uninstalling the app permanently deletes all saved dump and key files. Getting Started with 2.3.1
Source: Official builds are typically hosted on GitHub or F-Droid.
Setup: After installation, select "Read Tag" from the main menu and choose the standard key file to see if the tag can be mapped with default keys.
Writing: To clone a card, first "Read Tag" to create a dump, then use "Write Dump" to transfer that data to a compatible blank tag. MIFARE Classic Tool (MCT) - GitHub
MIFARE Classic Tool (MCT) is highly regarded by power users for being a straightforward, open-source Android utility for reading, writing, and analyzing MIFARE Classic RFID tags. While the current stable versions have advanced to 4.3.x, the core 2.3.1 era established the app's reputation for its reliable dictionary-attack key management and raw hex data manipulation. Why Users Rate It Highly
Dictionary Key Management: Users appreciate that it doesn't require knowing every key; it uses "key files" (dictionaries) to automatically authenticate sectors.
True Cloning Capabilities: It can create exact clones of tags, provided you use special "magic" tags that allow writing to the typically read-only manufacturer block (Sector 0).
No Fluff: Experts on platforms like GitHub and F-Droid value its technical transparency—there are no fancy GUIs, just raw hexadecimal access for precise control.
Community Trust: Being open-source ensures no hidden trackers or malicious code, which is critical for a tool interacting with security-sensitive hardware. Common User Feedback
While the app is a staple for RFID hobbyists, community reviews often highlight specific technical hurdles:
Watch a demonstration of how the tool interacts with MIFARE Classic 1K cards to verify data and test copying capabilities: MIFARE Classic 1K 13.56 MHz Card Copy Test YouTube• Mar 15, 2023 Critical Technical Limits
No Cracking: The app itself cannot "hack" or brute-force unknown keys due to Android's slow NFC protocol; you must provide the keys via a dictionary file.
Hardware Compatibility: Writing to Sector 0 requires "Gen2" or specific "magic" tags; standard original tags are hardware-locked and cannot be modified even with this tool. This guide covers the core functionalities of the
Device Support: Not all Android phones have NFC chips capable of interacting with MIFARE Classic technology (some manufacturers, like Google in newer Pixels, have removed the necessary support).
Are you looking to clone a specific card, or do you need help setting up a custom key dictionary for a new tag?
Older versions of Mifare Classic Tool - MCT (Android) | Uptodown
MIFARE Classic Tool (MCT) version 2.3.1 is a legacy build of the popular open-source Android application used for low-level interaction with MIFARE Classic RFID tags. While the current stable version has advanced to 4.3.1 as of early 2026, version 2.3.1 remains a reference point for users of older hardware or those tracking the tool's development history. Core Functionality
The app serves as a comprehensive interface for managing MIFARE Classic cards, which are widely used globally for public transit, building access, and parking.
Reading & Writing: Users can read tag data, edit it in a hex editor, and write it back to specific blocks.
Cloning: It supports "dump-wise" writing to create clones of existing tags.
Note: To create a perfect clone, you often need "Magic Tags" (Gen2) that allow writing to the typically read-only manufacturer block (Block 0).
Dictionary Attacks: The tool does not "crack" keys but uses a dictionary-based approach, testing known keys from a file to authenticate and read sectors.
Analysis Tools: It includes a "Diff Tool" to compare two tag dumps and encoders/decoders for access conditions and value blocks. Version 2.3.1 Highlights
Released around October 2020, this specific version included several targeted updates:
MIFARE Classic Tool (MCT) is an open-source Android application designed for interacting with MIFARE Classic RFID tags
. Version 2.3.1 (and its subsequent updates) serves as a specialized utility for researchers and hobbyists to read, write, and analyze the data stored on these widely used 13.56 MHz proximity cards Core Functionality
The tool operates by leveraging the NFC hardware in Android devices to perform several low-level tasks: Reading and Writing
: It can read data from MIFARE Classic 1k, 2k, or 4k tags and write data to them, provided the user has the correct authentication keys (Key A and Key B) Key Management
: Users can manage "dictionary" files containing potential keys to unlock encrypted sectors Data Analysis
: The app includes a "Diff Tool" to compare the contents of two different tag dumps, making it easier to identify which bits of data change during specific actions (like a balance decrease on a transport card)
: It allows users to create backups or clones of cards, which is particularly useful for consolidating access cards onto a single device or replacing a physical card with a compatible blank tag Technical Architecture
MIFARE Classic cards are structured into sectors, each containing multiple blocks. Security is managed through: Sector Trailers
: The final block in each sector stores the two authentication keys and the access conditions (which define if a block is read-only, writeable, etc.) Encryption
: While originally considered secure, the proprietary Crypto1 algorithm used by MIFARE Classic has known vulnerabilities, which MCT helps researchers explore Use Cases and Ethical Considerations MIFARE technology is ubiquitous in modern infrastructure: Public Transit & Access Open MCT and tap "Read Tag
: It powers transit systems, hotel room keys, and corporate ID badges Security Auditing
: Professionals use MCT to audit these systems for vulnerabilities, demonstrating how easily some cards can be duplicated or manipulated
Because MIFARE Classic Tool can be used to bypass security measures or manipulate balances, its use should be restricted to educational purposes or on hardware you own. You can find the application on platforms like for the open-source version or the Google Play Store specific technical vulnerabilities of the MIFARE Classic encryption or how to format a dictionary file for the tool? MIFARE type identification procedure - NXP Semiconductors
Mifare Classic cards (Standard 1K/4K) operate on the ISO/IEC 14443 Type A standard and are ubiquitous in physical access control systems, public transportation, and legacy payment systems. Despite being deprecated by NXP Semiconductors in favor of more secure alternatives (Mifare DESFire, Mifare Plus), the Classic series remains prevalent.
Mifare Classic Tool v2.3.1 serves as a low-cost, portable auditing platform. Unlike specialized hardware such as the Proxmark III, MCT leverages the NFC controller present in consumer smartphones, lowering the barrier to entry for physical security assessments.
MIFARE Classic Tool 2.3.1 is more than an app; it is a monument to open-source reverse engineering. It democratized RFID hacking, taking it from $1,000 Proxmark rigs to a $50 used Android phone.
If you are a security professional, download version 2.3.1, buy a set of Magic Cards, and test your own front door. You will likely be horrified by how easily it opens.
If you are a systems integrator: Stop using MIFARE Classic. Today. And if you must use it for legacy reasons, at least use diversified keys and monitor your readers for the unique RF patterns of a Nested Attack—specifically the version signature left by MCT 2.3.1.
The locks don't work if the keys are public. And thanks to MCT 2.3.1, the keys have been public for a very long time.
Disclaimer: This article is for educational purposes and authorized security testing only. Unauthorized access to RFID systems is a crime. Always obtain written permission before scanning or cloning any card you do not personally own.
MIFARE Classic Tool (MCT) , particularly version , is a specialized Android application designed for low-level interaction with MIFARE Classic RFID tags. While newer versions like 4.3.1 now exist, version 2.3.1 remains a significant milestone in the tool's history, often sought for its compatibility with older Android architectures or specific legacy devices. Google Play Core Capabilities of MCT 2.3.1
This open-source tool allows users to read, write, and analyze the data stored on 13.56 MHz high-frequency RFID tags. Its primary functions include: Data Reading & Analysis
: Users can read tag data using "key files" or dictionaries to authenticate against different sectors. The app displays this information in various formats, such as highlighted hex or 7-Bit US-ASCII. Tag Cloning
: MCT can perform "dump-wise" writing, effectively cloning the contents of one tag onto another, provided the target is a special rewritable tag (like a "Magic" card). Key Management
: It features a dictionary-based authentication system. Users can create, edit, and share key files to attempt access to protected sectors without knowing all keys beforehand. Technical Information
: The tool can identify and display generic tag information such as UID, SAK, ATQA, and memory size. Technical Constraints and Use Cases
MCT is intended for users with basic familiarity with MIFARE Classic technology. It is crucial to note its limitations: Google Play Hardware Dependency
: The app's functionality depends entirely on the device's NFC controller. Some modern smartphones do not support MIFARE Classic due to hardware restrictions. No Cracking Capability
: MCT cannot "crack" or "hack" keys through brute force, as the protocol is too slow for such methods. Access requires valid keys derived from external tools like a or other specialized software. Legacy Support
: Version 2.3.1 is specifically compatible with Android 4.3 and up, making it a "stable" choice for older hardware that might struggle with the latest updates. Ethical and Legal Considerations Older versions of Mifare Classic Tool - MCT (Android) 29 Jan 2026 —
Here is the organized content for Mifare Classic Tool (MCT) version 2.3.1. This content is structured for a release announcement, a download page, or a documentation README.
The Mifare Classic Tool (MCT) is an open-source Android application designed for analyzing and auditing Mifare Classic RFID tags. Version 2.3.1 represents a stable iteration of the tool, providing security professionals with the capability to read, write, clone, and analyze the access control mechanisms of some of the world's most deployed contactless smart cards. This paper outlines the technical architecture of MCT, details the vulnerabilities inherent to the Mifare Classic standard that the tool exploits, and discusses the ethical implications of its use in security auditing.