Developer Data Tools
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ID tool

UUID / GUID Generator & Validator

Generate UUID v4 values and validate UUID/GUID strings in the browser.

Tool Workspace

This tool runs in your browser. Developer Data Tools does not save pasted input to a server, but avoid using production secrets, access tokens, private keys or sensitive business data in any online page.

Ready. Processing runs in your browser.

Core Features

  • Generate random UUID v4 values with crypto.randomUUID.
  • Validate common UUID/GUID formats.
  • Identify version and variant bits.
  • Create local test identifiers quickly.

Common Errors

  • Treating UUID format validation as proof that an ID exists.
  • Using predictable IDs for secret URLs.
  • Mixing braces or uppercase with systems that require canonical lowercase strings.

Real Developer Use Cases

  • Creating request ids for local tests.
  • Checking copied GUIDs from logs.
  • Preparing example payloads.
JSON Formatter & Validator

Format and validate copied API responses.

Text Diff Checker

Compare generated output and source snippets.

Base64 Encoder/Decoder

Inspect encoded data fragments.