Random API Key Generator
Generate secure API keys with customizable formats and optional key-secret pairs
Our API key generator creates cryptographically secure tokens used for authenticating applications and services. Generate random API keys in multiple formats including alphanumeric, hexadecimal, Base64, Base64 URL-safe, UUID v4, and numeric formats. Perfect for REST API authentication, webhook secrets, service-to-service auth, and client application IDs. All keys use industry-standard CSPRNG to ensure maximum entropy and unpredictability. Generate single keys or bulk generate up to 25 keys at once. Optional key-secret pairs for enhanced security with separate public keys and private secrets. Export your API keys as text, CSV, or JSON for easy integration. Visit our API documentation for programmatic key generation.
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What is an API Key Generator?
An API key generator creates cryptographically secure tokens used for authenticating applications and services. Our generator uses industry-standard random byte generation to ensure maximum entropy and unpredictability.
API keys provide a simple authentication method where each key uniquely identifies a client application. They're perfect for server-to-server communication and public API access control.
API Key Generator Configuration Options
API Key Format Selection
- Alphanumeric (A-Za-z0-9): 62 characters, URL-safe, most versatile. Example: sk_vR8n2KmPqL4xWj9TcFaG. Entropy: ~5.95 bits/char.
- Hexadecimal (0-9a-f): 16 characters, compact binary representation. Example: api_4a7f3c9e2b8d1f6a5c3e. Entropy: 4 bits/char.
- Base64 (RFC 4648): 64 characters with +/=, most compact. Example: pk_8vR2xK/mL+3wN9Qa==. Entropy: 6 bits/char.
- Base64 URL-Safe: Replaces +/ with -_, no padding. Example: token_8vR2xK-mL_3wN9Qa. Used by JWT and OAuth.
- UUID v4 (RFC 4122): Standard 128-bit format. Example: key_f47ac10b-58cc-4372-a567-0e02b2c3d479. 122 bits randomness.
- Numeric Only (0-9): Digits only, lower entropy. Example: pin_74829365018293. For PINs and verification codes.
Key Length (8-256 Characters)
- 16 chars: Minimum for development/testing (48-96 bits entropy)
- 32 chars: Recommended for production (128-192 bits entropy)
- 40 chars: High security for financial APIs (160-240 bits entropy)
- 64 chars: Maximum security (256-384 bits entropy)
- 128+ chars: Paranoid security or compliance requirements
Custom Prefixes
- sk_ Secret Key - Private keys for server-side operations (Stripe pattern)
- pk_ Public Key - Client-side publishable keys
- api_ API Key - General-purpose API authentication
- test_ Test Environment - Development/staging keys
- prod_ Production - Live environment keys
Key-Secret Pairs (Dual Authentication)
- Public Key (ID): Identifies the application/client (can be logged safely)
- Secret Key (Credential): Proves ownership (never logged, encrypted in storage)
- Usage: Key in request headers, secret for HMAC signatures
- Examples: AWS Access Key ID + Secret, OAuth Client ID + Secret
Cryptographic Security Standards
- Entropy Source: Operating system CSPRNG with hardware randomness
- Standards Compliance: NIST SP 800-90A/B/C compliant
- Unpredictability: Computationally infeasible to predict keys
- Statistical Quality: Passes NIST randomness test suite
Common API Key Use Cases
- REST API Authentication: Simple bearer token for HTTP APIs
- Webhook Secrets: HMAC signing keys for payload verification
- Service-to-Service Auth: Backend microservice authentication
- Client Application IDs: Mobile app/SPA identification
- Rate Limiting Keys: Track and enforce API usage quotas
- CI/CD Pipeline Secrets: Automated deployment authentication
How to Generate Secure API Keys
[STEP 1] Configure Length
Set key length between 8-256 characters. We recommend at least 32 characters for production use.
[STEP 1] Select Format
Choose from alphanumeric, hex, base64, base64url, UUID, or numeric formats based on your needs.
[STEP 1] Optional Prefixes
Add prefixes like sk_, pk_, or api_ to identify key types and environments.
[STEP 1] Key-Secret Pairs
Enable key-secret pairs for two-factor authentication where the key identifies and secret proves ownership.
API Key Security Best Practices
- _ Never expose API keys in client-side code or public repositories
- _ Use environment variables to store keys in your applications
- _ Rotate API keys regularly, especially after team changes
- _ Implement key scoping to limit what each key can access
- _ Use different keys for development, staging, and production
- _ Monitor API key usage and implement rate limiting
Technical Implementation
Our API key generator employs cryptographically secure random number generation to produce tokens with maximum entropy. The system validates input parameters, generates random byte sequences, and applies format-specific encoding transformations to create the final keys.
// Mathematical entropy calculation entropy = key_length × log₂(character_set_size) // Character set sizes by format: alphanumeric: 62 chars | hex: 16 chars | base64: 64 chars // Example: 32-character alphanumeric key 32 × log₂(62) ≈ 190.3 bits of entropy