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Sync settings

Choose what your account keeps in step on every device where you are signed in.

  • My tools

    Always synced: the tools on your board, their order and size.

  • The windows open on your start page, including what you typed in them.

  • Every note in the notepad – on the notepad page, on your board and in windows.

  • Every list of website shortcuts – on the shortcuts page, on your board and in windows.

  • Every grid in the cover grid maker – on its page, on your board and in windows.

  • Every list of bookmarked organisations in the OIN lookup – on its page, on your board and in windows.

  • Keeps your pipeline and saved recipes on all your devices. Your files are never synced – only the steps and settings.

Turning something off removes it from your account straight away. Your devices keep their own copy.

Notifications

Tools that can tell you about something new while a Synsi tab is open, even when you are in another tab or app. Choose them for this browser.

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Notifications are blocked for this site. Allow them in your browser’s site settings (the icon left of the address), then switch them on here.

  • Says “New message” while a Synsi tab is open – never who wrote it or what.

Your choice is stored in this browser only. Notifications never show personal content such as a message or a number. They work while a Synsi tab is open; closed tabs get none.

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UUID Generator (v4 and v7)

Generate cryptographically random UUID v4 or sortable UUID v7 identifiers – one or hundreds at a time.

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Version
Runs in your browser – your data never leaves your device Also available via our free API

How to use the UUID Generator

  1. 1 Choose UUID version 4 (random) or version 7 (time-ordered).
  2. 2 Set how many you need and the format options.
  3. 3 Click Generate and copy or download the list.

What is a UUID?

A UUID (Universally Unique Identifier), also called a GUID, is a 128-bit identifier written as 32 hexadecimal digits in five groups: 550e8400-e29b-41d4-a716-446655440000. UUIDs can be generated anywhere, by anyone, without a central registry, and the chance of two being the same is negligible.

v4 or v7?

  • UUID v4 is fully random (122 random bits). It reveals nothing about when or where it was created and is the classic choice for IDs, tokens and file names.
  • UUID v7 starts with a millisecond timestamp followed by random bits, as defined in RFC 9562. UUIDs created later sort after earlier ones, which keeps database indexes compact and fast. It is the recommended choice for new primary keys.

Generated securely

UUIDs are generated in your browser with the Web Crypto API, a cryptographically secure random number generator, and are never sent to our servers.

Formatting options

Some systems expect uppercase UUIDs, or the 32-character form without hyphens. Toggle the options and the list updates on the next generation.

Frequently asked questions

Can two UUIDs ever be the same?

In theory yes, in practice no. With 122 random bits you would need to generate about a billion UUIDs per second for around 85 years to reach a 50% chance of a single duplicate.

Is a GUID the same as a UUID?

Yes. GUID is Microsoft’s name for the same 128-bit identifier format.

Should I use UUID v7 for database keys?

Usually yes. Because v7 values increase over time, inserts land at the end of the index, which is much faster than inserting random v4 values in large tables.

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