Bulk Time-Based UUID Generator (v1)
Generate multiple time-based version 1 UUIDs instantly in your browser.
Time-Based UUIDs
A version 1 UUID is generated using a combination of the computer's MAC address and a 60-bit timestamp representing the number of 100-nanosecond intervals since October 15, 1582. Because the timestamp component naturally increases, v1 strings often cluster together when sorted lexically.
This tool implements a privacy-first approach by spoofing the MAC address. Instead of extracting your real hardware address, we generate a random 48-bit node ID and set the IEEE 802 multicast bit, adhering to the RFC 4122 spec without leaking local data.
Format Options
- Quantity: Enter any number up to 5,000 to batch generate UUIDs for database seeding.
- Hyphens: Checked by default (8-4-4-4-12 format). Uncheck to output raw 32-character hexadecimal strings.
- Uppercase: Convert standard lowercase characters to uppercase, required by legacy enterprise systems.
- Braces: Wraps the identifier in curly braces, creating the standard Microsoft GUID structure.
Frequently Asked Questions
What is a UUID v1?
A version 1 UUID is a time-based identifier defined by RFC 4122. It is generated using the computer's MAC address and a high-precision timestamp based on the Gregorian epoch (October 15, 1582). This ensures uniqueness across both space (MAC address) and time.
UUID v1 vs v4: Which should I use?
Use UUID v4 for general purposes, as it is completely random and provides better privacy. Use UUID v1 only when your database explicitly requires time-ordered sequential indexing or when you need to embed chronological data directly into the identifier.
Does UUID v1 expose my MAC address?
Historically, yes. However, modern implementations (like this web tool) generate a random 48-bit node ID with the multicast bit set instead of reading your actual hardware MAC address. This preserves the structural integrity of the v1 format while maintaining your privacy.