Seed databases and test data
Generate multiple UUIDs quickly when you need identifiers for seeded records, fixtures, or quick test payloads.
Generate UUID v4 identifiers instantly, choose how they are formatted, copy the output, and download full batches for development, testing, seeding, and integration work.
Generate random UUID v4 identifiers instantly with format and output controls.
Generate multiple UUIDs quickly when you need identifiers for seeded records, fixtures, or quick test payloads.
Create UUIDs for request examples, resource IDs, sessions, object references, and integration testing workflows.
Switch the output style when a project needs uppercase UUIDs, no hyphens, braces, URN formatting, or JSON-friendly output.
Generate a small batch of UUIDs and paste them into sample JSON payloads when you need realistic resource IDs for development work.
Create a larger set of UUIDs in one run and download them as text when you need identifiers for fixture data or seeded records.
Switch the format to no hyphens if a library, storage layer, or import flow expects compact UUID strings.
Choose JSON array output when the identifiers need to drop directly into mock data, API examples, or config files.
The generator creates UUID v4 identifiers in the browser using modern random UUID support when available, with a safe fallback for environments that do not expose that API directly. That keeps the result fast and browser-based while still covering common development use.
After the UUIDs are generated, the tool formats them based on the option you choose. You can keep the standard lowercase version or change the output to uppercase, no hyphens, braces, or URN format depending on what the next system expects.
The final output can be displayed one per line, comma separated, or as a JSON array, which makes it easier to move the result into code, scripts, API payloads, config files, test fixtures, or database workflows.
Use the JSON Formatter when the same workflow also needs cleaner payloads around the generated IDs.
Open the Username Generator if the workflow also includes public handles, names, or profile identity work.
Try the Fake Address Generator when your test set also needs sample profile or address data alongside UUIDs.
A UUID generator is useful because development work often needs unique identifiers before the rest of a system is even running. This page helps you create those IDs quickly without opening a terminal, library docs, or a separate coding environment just to get a few valid UUIDs.
It works well for app prototypes, APIs, seeded records, mock responses, sample payloads, session identifiers, and internal references when you need real UUID-looking output fast and in a format you can actually paste into the next step.
Use it when testing APIs, creating mock data, wiring sample objects, seeding records, or generating quick identifiers for development demos and early system work.
Different tools expect UUIDs in different forms. Some need standard lowercase values, while others expect uppercase, compact strings without hyphens, braces, URN prefixes, or JSON-ready output.
Copy the identifiers into your app, API payload, fixture file, config, or database script, or download the full output when the UUID list needs to be saved for later development work.