What is a secret key used for?

Secret keys are used for cryptographic operations like encryption/decryption, digital signatures, JWT token signing, HMAC generation, and API authentication. They must be kept confidential and secure.

How secure are the generated secret keys?

All secret keys are generated using cryptographically secure random number generation (crypto.getRandomValues()). Keys are generated locally in your browser and never transmitted to servers.

What key formats are available?

We support multiple formats including hexadecimal, Base64, Base64 URL-safe, raw bytes, and JWT-compatible keys. Each format is suitable for different cryptographic applications.

What key length should I use?

For AES encryption: 128, 192, or 256 bits. For HMAC: 256+ bits. For JWT: 256+ bits. For general APIs: 256+ bits. Longer keys provide better security but check your application requirements.

Secret Key Generator

Generate cryptographically secure secret keys for encryption, JWT tokens, API authentication, and security applications. Multiple formats and industry-standard presets.

Secret Key Generator

Generate cryptographically secure secret keys for various applications

Key Preset

Output Format

Key Length (bits)

Must be divisible by 8. Common lengths: 128, 192, 256, 384, 512 bits.

Preset: Custom key length (256-bit)

Format: Hexadecimal format (0-9, A-F) - Most common for encryption keys

Key Features

Industry-standard key presets (AES, HMAC, JWT)

Multiple output formats (Hex, Base64, JWT-safe)

Cryptographically secure random generation

Custom key lengths (128-1024 bits)

Key visibility toggle for security

Generation history with metadata

Understanding Secret Keys

Encryption Keys: Symmetric keys for AES encryption/decryption

HMAC Keys: Keys for message authentication codes

JWT Secrets: Keys for signing JSON Web Tokens

API Keys: Authentication tokens for secure API access

Security Best Practices

Keep Secret: Never share or expose secret keys publicly

Secure Storage: Use environment variables or key vaults

Key Rotation: Regularly replace keys in production

Access Control: Limit who can access secret keys

Environment Separation: Use different keys per environment

Audit Trails: Log key usage and access patterns

Backup Strategy: Securely backup keys with encryption

Compliance: Follow industry standards (NIST, FIPS, SOC2)

Security Notice

All keys are generated locally using cryptographically secure methods. Keys are never transmitted to servers. Always follow your organization's key management policies and store keys securely.

Frequently Asked Questions

What's the difference between key presets?

AES keys are for encryption (128/192/256-bit), HMAC keys for message authentication (256-bit), and JWT keys for token signing (512-bit recommended). Each preset matches industry standards.

Which output format should I use?

Hex for most encryption libraries, Base64 for web APIs, Base64 URL-safe for URLs/filenames, JWT format for JSON Web Tokens, and raw bytes for low-level programming.

How should I store secret keys?

Use environment variables, key management services (AWS KMS, Azure Key Vault), or secure configuration files. Never hard-code keys in source code or store in databases.

How often should I rotate secret keys?

Rotate keys regularly based on risk: high-security applications every 30-90 days, general applications every 6-12 months, or immediately if compromise is suspected.

Is AES-128 still secure in 2024?

Yes, AES-128 remains secure for most applications. However, AES-256 is recommended for high-security environments, government applications, or long-term data protection (10+ years).

Can I use the same key for multiple purposes?

No! Never reuse keys across different purposes. Use separate keys for encryption, signing, and authentication. Key reuse can lead to cryptographic vulnerabilities and security breaches.

How do I handle key compromise or suspected breach?

Immediately rotate the compromised key, revoke access, audit all systems using that key, investigate the breach scope, and implement additional monitoring. Have an incident response plan ready.

What's the difference between development and production keys?

Use separate keys for each environment. Development keys can be shorter for convenience, but production keys must follow security standards. Never use production keys in development.

Are these keys FIPS 140-2 compliant?

The Web Crypto API uses FIPS-approved algorithms, but browser implementation may not be FIPS certified. For FIPS compliance, use dedicated hardware security modules (HSMs) or certified libraries.

Should I use derived keys or random keys?

Random keys (like this tool generates) are preferred for most use cases. Use key derivation functions (KDF) only when you need deterministic keys from passwords or need hierarchical key structures.

How do performance requirements affect key choice?

AES-128 is fastest, AES-256 adds ~40% overhead. HMAC-SHA256 is efficient for signing. For high-throughput applications, benchmark your specific use case to choose optimal key lengths.

What's the entropy quality of browser-generated keys?

Modern browsers use high-quality entropy sources (hardware RNG, OS entropy pools). The Web Crypto API provides cryptographically secure randomness suitable for production use.