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Gerador UUID

Gerar identificadores UUID/GUID aleatórios

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Como Usar

1

Insira Seus Valores

Preencha os campos de entrada com seus números ou parâmetros.

2

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Os resultados são atualizados automaticamente enquanto você digita — sem botão de envio necessário.

3

Copie ou Salve

Copie os resultados para a área de transferência ou use-os no seu fluxo de trabalho.

Por Que Usar Esta Ferramenta

100% Gratuito

Sem custos ocultos, sem planos premium — todos os recursos são gratuitos.

Sem Instalação

Funciona inteiramente no seu navegador. Nenhum software para baixar ou instalar.

Privado e Seguro

Seus dados nunca saem do seu dispositivo. Nada é enviado a nenhum servidor.

Funciona no Celular

Totalmente responsivo — use no seu celular, tablet ou desktop.

UUIDs: Universally Unique Identifiers Explained

Key Takeaways

  • UUIDs (v4) use 122 bits of randomness to generate identifiers that are statistically guaranteed to be unique across all systems worldwide.
  • UUID v4 is the most common version — purely random with no embedded timestamp or machine information.
  • All UUIDs are generated in your browser using cryptographic randomness — nothing is stored or transmitted.

Universally Unique Identifiers (UUIDs) solve the fundamental distributed systems problem of generating unique identifiers without central coordination. Whether you are building microservices, designing database schemas, or creating distributed systems, UUIDs provide a standardized way to create identifiers that will never collide, even across independent systems.

The probability of generating two identical UUID v4 values is approximately 1 in 5.3 x 10^36.

Collision Probability

Key Concepts

1

UUID Versions

UUID v1 uses timestamp + MAC address. V3 uses MD5 namespace hashing. V4 uses pure randomness. V5 uses SHA-1 namespace hashing. V7 (new) combines timestamp with randomness for sortability.

2

UUID v4 Structure

A UUID v4 follows the format xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx where '4' indicates version 4 and 'y' is constrained to 8, 9, a, or b to indicate the variant. The remaining 122 bits are random.

3

UUID vs. Auto-Increment IDs

Auto-increment IDs are sequential and predictable, leaking information about record count and creation order. UUIDs are random and reveal nothing, making them better for public-facing identifiers.

4

UUID v7 — The New Standard

UUID v7 (RFC 9562) embeds a Unix timestamp in the first 48 bits, making UUIDs naturally sortable by creation time while maintaining randomness. This is ideal for database primary keys.

Pro Tips

Use UUID v7 for database primary keys — the embedded timestamp makes them naturally sortable, improving B-tree index performance.

Store UUIDs as binary (16 bytes) in databases rather than as strings (36 characters) for significant storage and performance gains.

Remove hyphens when UUIDs are used in URLs to keep them compact while maintaining readability.

Use crypto.randomUUID() in modern browsers — it is faster and more secure than JavaScript UUID libraries.

All UUIDs are generated entirely in your browser using the Web Crypto API. No generated identifiers are stored, logged, or transmitted to any server.

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