Key Size Calculator
Convert a cryptographic key size between bits, bytes, hex, and Base64. Enter your values, click Calculate, and get the full result with its breakdown — everything is processed on your device, nothing is sent to a server.
All calculations run in your browser. Your data is never sent to our servers.
Example
Example Input
256 bits
Example Output
32 bytes, 64 hex chars, keyspace 2^256
How to Use
- 1Fill in each input field with the values you want to compute.
- 2If there are choices (units, mode, operation), pick what you need.
- 3Click the Calculate button (or press Ctrl+Enter).
- 4The main result and its breakdown appear in the Result area. Click Copy to copy it.
About the Key Size Calculator
The Key Size Calculator converts a key size from bits to bytes, hex character count, and Base64 characters — plus the keyspace (2ⁿ). Useful when choosing key lengths (AES-128/256, etc.) and understanding their representation.
Helps estimate key strength and storage format.
FAQ
Is this Key Size Calculator accurate?
Yes. It uses standard formulas and runs directly in your browser at full JavaScript precision (plus BigInt/decimal.js for large numbers where needed).
Is my data sent to a server?
No. All calculations happen entirely on your device. No values are sent to or stored on our servers.