RFID キーフォブとアクセスカードをコピーする方法

RFID キーフォブとアクセスカードをコピーする方法: 完全ガイド

RFID key fobs and Access Cards are common tools for modern access control. They let authorized users unlock doors, enter offices, or access secure areas with a simple tap.

But what if you lose your RFIDキーフォブ or need an extra copy for family or staff? This guide explains how copying works, which chips can be duplicated, and what legal and security precautions to follow.

Quick Checklist: How Copying Works

Before diving in, here’s a simple 4-step summary you can follow:
Scan → Write → Test → Register

Scan your original RFIDキーフォブ using a compatible USB RFID copier.
Write the stored data to a blank RFID tag or card.
Test the new tag on your door or reader.
Register it with your system administrator if needed.
⚠️ Note: Only copy RFID key fobs or Access Cards that you own or are authorized to duplicate. Unauthorized duplication may be illegal and compromise system security.

What Is an RFID Key Fob and How Does It Work?

アン RFIDキーフォブ is a small wireless device that uses Radio Frequency Identification (RFID) to communicate with a reader. When tapped on a reader, it transmits a unique ID number that the access system recognizes and grants entry.

Core Features

利便性： Tap-and-go entry without keys.
耐久性: Withstands daily use.
Customizable Access: Programmed for specific users or areas.

These fobs and RFIDカード are used in apartments, offices, parking systems, and schools.

Why Copy RFID Key Fobs or Access Cards?

利便性： Give family members or staff their own fobs.
Backup: Avoid lockouts if the original is lost.
Shared Access: Simplify entry for cleaning staff, guests, or short-term rentals.

Having a backup RFID Card ensures access continuity without waiting for replacements.

Understanding Chip Types and Copy Difficulty

Not all RFID key fobs can be cloned. Copying depends on the frequency and chip type inside the card or fob.

1. 125 kHz Low Frequency (LF) – EM4100 / HID Prox

Common use: older building systems.
Copying: relatively easy with a basic USB RFID copier and blank 125 kHz tags.
プロセス： scan → write → test → register.

2. 13.56 MHz High Frequency (HF) – MIFARE Classic

Common use: offices, schools, transport cards.
Copying: possible only if encryption is weak or absent.
Tools: an advanced copier that supports MIFARE Classic.

3. DESFire / HID iCLASS / SEOS (Encrypted Smart Cards)

Common use: enterprise or government systems.
Copying: typically not possible without admin credentials.
Best practice: Request an official duplicate from your building manager.
Tip: Check the frequency label on your RFID Card or scan it with an RFID reader to identify chip type before attempting duplication.

Tools You’ll Need

To copy an RFID key fob or card correctly, prepare the following:

RFID copier or duplicator – to read and write data.
Blank RFID tags or cards – to create new copies.
Original RFID key fob – the source credential.
(Optional) NFC smartphone app – limited use for some 13.56 MHz tags.

You can browse Blank 125 kHz RFID Tags そして RFID Cards for Access Control from reliable suppliers.

Can I Copy an RFID Key Fob with My Phone?

Some NFC-enabled smartphones can read and emulate 13.56 MHz RFID Cards, but they can’t clone encrypted fobs.

Works with: unprotected MIFARE Classic or NTAG chips.
Does not work with: HID iCLASS, SEOS, or DESFire.
Extra hardware: may be required for writing to physical cards.

Security Risks and How to Stay Safe

Copying RFID key fobs without oversight can create security issues:

Unauthorized access: duplicates could be misused.
Unencrypted data: Older fobs are easier to clone.
Data theft: insecure readers might leak information.
Best practices:
Use encrypted or secure RFID Cards.
Rotate access credentials regularly.
Monitor entry logs for unusual patterns.

Enhancing Access Control Security

To strengthen your system:

Upgrade to encrypted fobs (MIFARE DESFire or HID iCLASS).
Enable two-factor access: combine RFID with PIN or biometrics.
Track user activity: use software logs to detect anomalies.
“A properly encrypted RFID key fob reduces cloning risk and protects your entire facility.”

RFID vs. NFC: Quick Comparison

特徴	RFID	非対称
範囲	最大数メートル	数センチ
Typical use	Access control, logistics	Mobile payments, smartcards
Duplication difficulty	Moderate to high	Very high (due to encryption)

Both use radio frequency, but NFC is more secure and typically used for smartphones and payment systems, while RFID key fobs are optimized for door entry and identification.

Encryption in Modern RFID Cards

Encryption protects the communication between the RFID card and reader, making unauthorized copying nearly impossible.
利点：

Prevents data duplication.
Preserves data integrity.
Future-proofs your system against attacks.
Switching to encrypted RFID Cards is one of the easiest ways to prevent unauthorized copies.

RFID キーフォブとアクセスカードに関するよくある質問

キーフォブが暗号化されているかどうかはどうすればわかりますか?

Encrypted fobs usually require proprietary software or special readers. If a basic copier can’t read it, it’s likely encrypted.

自宅で RFID キーフォブを複製できますか?

Yes, you can with a compatible RFID copier and blank tags, but only if you have permission to duplicate them.

RFID と NFC の違いは何ですか?

RFID has a longer range and multiple frequency bands; NFC is short-range and used mainly in smartphones.

Is it legal to copy an RFID access card?

Copying without authorization can violate privacy or property rules. Always get approval from the system owner.

What are the common frequencies?

125 kHz (LF) and 13.56 MHz (HF) are most common for key fobs and access cards.

結論

RFID key fobs and Access Cards are powerful tools for security and convenience — but duplicating them requires understanding of chip types, tools, and legal limits.
When in doubt, seek help from a certified RFID technician or request an official replacement from your building management.