How to Generate UUIDs Online
Set the Count
Enter how many identifiers you need in the Count field. You can request anywhere from 1 to 100 UUIDs in a single batch, which is handy for seeding test fixtures or filling a column of sample data.
Pick a Format
Choose Standard lowercase, UPPERCASE, No hyphens, or Braces from the Format menu. The display updates the moment you click Generate, so you can match the exact style your database, config file, or code expects.
Generate and Copy
Click Generate UUIDs to produce the batch in the output box, then use Copy All to send every value to your clipboard at once. Each UUID sits on its own line, ready to paste straight into your editor.
Output Format Options Compared
This generator produces version 4 (random) UUIDs and lets you reshape the text into four common styles. The underlying value is identical in every case; only the casing, hyphens, and wrapping change. Pick the style your target system parses most cleanly.
| Format | Example Shape | Hyphens | Typical Use |
|---|---|---|---|
| Standard (lowercase) | xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx | Yes | Default for APIs, JSON, and most databases |
| UPPERCASE | XXXXXXXX-XXXX-4XXX-YXXX-XXXXXXXXXXXX | Yes | Legacy systems and some Microsoft tooling |
| No hyphens | xxxxxxxx xxxx 4xxx yxxx xxxxxxxxxxxx (joined) | No | Compact keys, URLs, and file names |
| Braces | {xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx} | Yes | Windows registry GUIDs and COM identifiers |
| Count range | 1 to 100 per batch | n/a | Single value or bulk test data |
| Version | UUID v4 (random) | n/a | General-purpose unique identifiers |
Which Format Should You Use
Database Primary Keys
Use the Standard lowercase format. It matches the canonical UUID text representation expected by PostgreSQL uuid columns, MySQL CHAR(36), and most ORMs without extra conversion.
Windows or .NET GUIDs
Choose Braces or UPPERCASE. Registry entries, COM class IDs, and some .NET tooling display GUIDs wrapped in curly braces or in capital letters by convention.
URLs and File Names
Pick No hyphens for a compact 32-character string. Removing the dashes keeps identifiers tidy in slugs, object storage keys, and temporary file names.
Bulk Test Data
Set the Count up to 100 and use Copy All. This fills seed scripts, mock responses, or spreadsheet columns with distinct identifiers in one paste.
Common Problems and Fixes
Copy All does nothing
The Copy button uses the browser clipboard API, which requires a secure context. Make sure you are on the https version of the page and that the output box is not empty before clicking Copy All.
I asked for more than 100
The Count is capped at 100 per batch and clamped to a minimum of 1. If you typed a larger or invalid number it is reduced to 100; simply click Generate again to produce additional batches.
The output looks the same every refresh
The tool auto-generates one UUID when the page loads. Click Generate UUIDs to create a fresh batch, or change the Count or Format first and then generate.
I need version 1 or version 5 UUIDs
This tool produces version 4 random UUIDs only. It does not create time-based (v1) or name-based (v3/v5) identifiers, so use a dedicated library if your system specifically requires those versions.