MAC 地址生成器
为测试和开发生成随机 MAC 地址
生成
使用方法
输入数值
在输入栏中填入您的数字或参数。
即时获取结果
结果在您输入时自动更新——无需按计算按钮。
复制或保存
将结果复制到剪贴板或用于您的工作流程。
为什么使用此工具
100% 免费
没有隐藏费用，没有付费等级——所有功能完全免费。
无需安装
完全在浏览器中运行。无需下载或安装任何软件。
隐私且安全
您的数据永远不会离开您的设备。不会上传至任何服务器。
支持移动设备
完全响应式设计——在手机、平板或桌面电脑上均可使用。
MAC Addresses: Hardware Identification in Networks
Key Takeaways
- MAC (Media Access Control) addresses are 48-bit hardware identifiers assigned to network interface cards for Layer 2 communication.
- The first 3 bytes (OUI) identify the manufacturer, while the last 3 bytes are device-specific — except in randomly generated addresses.
- All MAC address generation is performed in your browser — no addresses are stored or transmitted.
MAC addresses are the physical identity of network devices, operating at Layer 2 of the OSI model. Every Ethernet frame and WiFi packet uses MAC addresses for local network delivery. Understanding MAC address structure is essential for network administration, security (MAC filtering), virtualization (VM network config), and troubleshooting connectivity issues at the data link layer.
The 48-bit MAC address space supports 281 trillion unique addresses — enough for every networked device on Earth.
Address Space
Key Concepts
MAC Address Structure
A MAC address has 6 octets (e.g., AA:BB:CC:DD:EE:FF). The first 3 octets form the OUI (Organizationally Unique Identifier) assigned to manufacturers. The last 3 are device-specific.
Unicast vs. Multicast Bit
The least significant bit of the first octet determines if the address is unicast (0, single device) or multicast (1, group of devices). Randomly generated addresses should set this bit to 0.
Local vs. Universal Bit
The second least significant bit of the first octet indicates whether the address is universally administered (0, manufacturer-assigned) or locally administered (1, custom/random).
MAC Address Randomization
Modern operating systems (iOS, Android, Windows) randomize MAC addresses when scanning for WiFi networks to prevent tracking. This uses the locally administered bit to distinguish from real hardware addresses.
Pro Tips
Set the locally administered bit (second-least significant bit of first octet) when generating random MAC addresses to avoid conflicting with real hardware.
Use consistent MAC addresses for VMs and containers in development to avoid DHCP lease issues when recreating environments.
MAC filtering provides minimal security — MAC addresses can be easily spoofed. Use 802.1X authentication for real network access control.
Common MAC address formats include colon-separated (AA:BB:CC:DD:EE:FF), hyphen-separated (AA-BB-CC-DD-EE-FF), and Cisco format (AABB.CCDD.EEFF).
All MAC address generation is performed entirely in your browser. No generated addresses are stored, logged, or transmitted to any server. Generated addresses are random and not associated with any real hardware.