API Key Generator

🔒 Security Best Practices

Never commit to version control: Keep API keys out of Git repositories and public code. Use environment variables: Store keys in .env files or secure configuration systems. Implement key rotation: Regularly generate new keys and deprecate old ones. Restrict permissions: Limit API key access to only necessary resources and operations. Monitor usage: Track API key usage for suspicious activity. Use HTTPS only: Always transmit API keys over encrypted connections.

📚 Understanding API Keys & Tokens

API keys are secret tokens that authenticate and authorize access to APIs and services. They act as passwords for your applications, allowing secure communication between systems while controlling access and tracking usage.

What Are API Keys?

API keys are unique identifiers used to authenticate requests to an API. When you make a request to a service, you include your API key (typically in the header or URL) and the server validates it before processing. API keys serve multiple purposes: they verify your identity, control access to specific resources, track usage and enforce rate limits and provide a way to revoke access without changing the entire system.

Key Formats and When to Use Each:

• Alphanumeric (A-Z, a-z, 0-9) - The most versatile and widely compatible format. Works in all systems including URLs, headers and configuration files. Best for REST API authentication tokens, general-purpose API keys and OAuth client secrets. Recommended length: 32-64 characters. Example: k8mP3nQr9sWv2xY5z7A4bC6dE8fG1hJ3
• Hexadecimal (0-9, a-f) - Compact binary data representation. Efficient for systems that work with binary data. Perfect for webhook secrets, HMAC signatures and cryptographic operations. Recommended length: 32-64 characters (16-32 bytes of entropy). Example: a1b2c3d4e5f6789012345678901234567890abcdef
• Base64 (A-Z, a-z, 0-9, +, /) - Standard data encoding format with high information density. Excellent for encoding binary data as text and JWT tokens. Good for database authentication tokens and session identifiers. Recommended length: 32-88 characters. Note: Use URL-safe base64 variant (replacing + with - and / with _) for URLs. Example: K8mP3nQr9sWv2xY5z7A4bC6dE8fG1hJ3lMnO
• UUID v4 (RFC 4122) - Standardized globally unique identifier format. Generates 128-bit random identifiers with extremely low collision probability. Perfect for database primary keys, distributed system identifiers and correlation IDs. Fixed length: 36 characters (32 hex + 4 hyphens). Example: 550e8400-e29b-41d4-a716-446655440000

Security Best Practices:

• Secure Storage: Never hardcode API keys in source code. Use environment variables (.env files) for local development. Store production keys in secure secret management systems like AWS Secrets Manager, HashiCorp Vault, Azure Key Vault or Google Cloud Secret Manager. Keep .env files out of version control using .gitignore.
• Key Rotation: Implement regular key rotation policies (every 90 days for high-security systems). Generate new keys before revoking old ones to prevent downtime. Maintain a grace period where both old and new keys work. Automate rotation using secret management tools.
• HTTPS Only: Always transmit API keys over encrypted connections (HTTPS/TLS). Never send keys in URL query parameters where they can be logged. Use request headers (Authorization header) or request body. Ensure your API only accepts HTTPS connections.
• Monitoring and Auditing: Log all API key usage with timestamps and IP addresses. Set up alerts for unusual patterns (high request rates, failed authentications, access from unexpected locations). Implement rate limiting to prevent abuse. Regularly review access logs for suspicious activity.
• Access Control: Follow the principle of least privilege - grant minimum necessary permissions. Use different API keys for different environments (development, staging, production). Implement scoping to restrict keys to specific resources or operations. Create separate keys for each service or application.
• Key Expiration: Set expiration dates for API keys when possible. Use short-lived tokens for temporary access. Implement automatic revocation for expired keys. Force renewal for long-term keys.

Common Use Cases:

• REST API Authentication: Standard authentication for web APIs. Keys sent in Authorization header or custom header. Used by services like Stripe, SendGrid and Twilio. Typically 32-64 character alphanumeric keys.
• Webhook Secrets: Verify webhook authenticity using HMAC signatures. Sender creates signature using secret key and request body. Receiver validates signature to confirm request origin. Prevents webhook spoofing and tampering. Use 64-character hexadecimal keys.
• Database Authentication: Connection strings for database access. Authenticate applications to databases (MongoDB, PostgreSQL, Redis). Often combined with username/password. Use 48-64 character base64 or alphanumeric tokens.
• Session Tokens: Identify user sessions after login. Stored in cookies or local storage. Short-lived tokens (hours to days). Used for stateless authentication in web applications. 32-48 character alphanumeric or base64 keys.
• Service-to-Service Authentication: Backend services communicating securely. Machine-to-machine authentication. Often combined with mTLS or OAuth 2.0. Long-lived, high-security keys (64+ characters).
• API Rate Limiting: Track and limit request rates per key. Prevent abuse and ensure fair usage. Associate keys with usage quotas. Monitor consumption and send alerts near limits.

Key Length Recommendations:

• 32 characters: Minimum for production REST API keys (128 bits entropy)
• 48 characters: Recommended for sensitive APIs and database tokens (192 bits)
• 64 characters: High security webhook secrets and long-term keys (256 bits)
• 128 characters: Maximum security for critical infrastructure (512 bits)
• 36 characters (UUID): Fixed length for globally unique identifiers (128 bits)

What NOT to Do:

• Never commit API keys to Git repositories or public code
• Never send keys in URL query parameters (they get logged)
• Never use predictable or sequential keys
• Never reuse the same key across multiple applications
• Never store keys in plain text files or spreadsheets
• Never share keys via email, chat or unencrypted channels
• Never use keys shorter than 32 characters for production
• Never ignore key rotation policies

⚠️ Security Note: All API keys are generated locally in your browser using the Web Crypto API. Nothing is transmitted to servers. Use this tool offline for maximum privacy. The keys are cryptographically secure and suitable for production use.