Free UUID / GUID Generator – Generate RFC 4122 Version 4 UUIDs
The NexVaani UUID / GUID Generator creates cryptographically secure, standard RFC 4122 Version 4 UUIDs for software engineers and database architects. Generate single UUIDs or batches of up to 500 identifiers with uppercase/lowercase and hyphen options.
The NexVaani UUID Generator produces standard RFC 4122 version 4 universally unique identifiers using the browser-native crypto.randomUUID() API.
Smart 1-Click Workflow Chains (Next Steps):
Real-World Use Cases & Applications
- Generating unique primary keys for PostgreSQL, MySQL, and MongoDB databases.
- Creating distributed tracing IDs (traceparent, request-id) for microservices.
- Generating unique mock IDs for unit tests and seed database fixtures.
NexVaani ツールの透明性
処理場所、ネットワーク動作、データ保持の技術的な説明
対応ツールはクライアントサイド技術によりWebブラウザー内でローカル実行されます。
計算やテキスト変換はブラウザー内でローカルに実行されます。
一時処理データはブラウザー内で処理され、NexVaaniには保存されません。
エクスポートされたファイルに透かし、スタンプ、ブランド表示は追加されません。 Output quality depends on your source file and selected settings.
使い方 UUID / GUID Generator （ステップごと）
Choose Quantity
Select how many UUIDs you want to generate (1 to 500).
Select Formatting
Choose uppercase/lowercase and include or strip hyphens.
Click Generate
Generate cryptographically random UUIDs in browser memory.
Copy UUIDs
Copy individual IDs or copy the full list to your clipboard.
技術アーキテクチャと実行の仕組み
RFC 4122 Version 4 UUID Collision Probability
A Version 4 UUID contains 122 random bits, yielding 2^122 (approx 5.3 x 10^36) unique values. The probability of generating a duplicate UUID is so infinitesimal that one would need to generate 1 billion UUIDs per second for 85 years to achieve a 50% collision chance.
UUID_v4 = xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx (where y in [8, 9, A, B])技術的な制限と運用上の制約
- Generates Version 4 (random) UUIDs. Version 1 (time-based) and Version 5 (namespace SHA-1) are not generated by this tool.
主な仕様と機能
- W3C Web Crypto Randomness – Uses crypto.randomUUID() for high collision resistance
- Bulk Generation – Generate up to 500 unique UUIDs in one click
- Format Customization – Toggle uppercase, lowercase, and hyphens (with or without dashes)
- Instant Copy & Export – Copy all IDs to clipboard or download as a text file
よくある質問と回答
What is the difference between a UUID and a GUID?
UUID (Universally Unique Identifier) and GUID (Globally Unique Identifier) are terms for the same 128-bit identifier standard defined in RFC 4122.
Can two generated UUIDs ever collide?
The chance of a collision with UUID v4 is practically zero (~1 in 2^122).
Are my files uploaded, analyzed, or stored on NexVaani servers?
Where supported, tool inputs and files are processed locally inside your web browser using WebAssembly and HTML5 Canvas. Your files are not uploaded to NexVaani file-processing servers.
評価 UUID / GUID Generator
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