online rsa calculator

Generate RSA keys, encrypt and decrypt messages using the RSA algorithm with this free online calculator.

Request Feature / Support

13,600+

Total Calculations Run

< 15ms

Browser Execution Speed

100%

Client-Side Privacy

4.9 / 5.0

User Satisfaction

AI Web Tool Generator

Build Your Own Custom Web Calculator in Seconds

Type what tool or calculator you need below. Our AI will build it instantly for your site.

About This Tool

This RSA calculator tool allows you to perform complete RSA cryptographic operations including generating RSA key pairs (public and private keys), encrypting messages with the public key, and decrypting them with the private key. The tool implements the full RSA algorithm with support for custom prime numbers, modulus calculation, Euler's totient function, and modular exponentiation. You can either generate random prime numbers or input your own values for complete control over the cryptographic process. The interface provides clear visualization of each step including modulus (n), public exponent (e), private exponent (d), and the results of encryption and decryption operations.

Save your calculation history with a free account

How to Use

Choose to generate random primes or enter your own prime numbers (p and q)
Enter a public exponent (e) or use the default 65537
Enter a message to encrypt (text or numbers)
Click 'Calculate RSA' to generate keys and perform encryption/decryption
View the results including modulus, private key, encrypted ciphertext, and decrypted plaintext
Use the 'Clear' button to reset all fields and start over

Frequently Asked Questions

Find Quick Answers

What is RSA encryption?

RSA is a public-key cryptosystem that uses two keys: a public key for encryption and a private key for decryption. It's based on the mathematical difficulty of factoring large prime numbers.

What prime number sizes should I use?

For security, use primes with at least 1024 bits (about 308 decimal digits). This calculator supports smaller values for demonstration and testing purposes.

Can I use my own prime numbers?

Yes, you can enter any two distinct prime numbers in the input fields. The tool will validate they are prime and calculate the RSA parameters accordingly.

What is the public exponent (e)?

The public exponent is typically 65537 (0x10001) as it's a prime number that allows for efficient encryption while maintaining security. You can use other values like 3 or 17 for testing.

Is this tool secure for real encryption?

This is an educational tool for understanding RSA. For real-world encryption, use established cryptographic libraries with proper key management and larger prime sizes.

Need to run multiple calculations?

Create a free account today to unlock unlimited daily runs, access advanced parameters, save your history, and request custom features.

Related Tools

Other useful calculators and utilities you might like

Spotify to MP3 Converter

Convert Spotify tracks and playlists to MP3 format instantly with our free online converter.

Road Distance Calculator

Calculate the driving distance and travel time between two addresses with our free online road dista...

Age Calculator

Calculate your exact age in years, months, and days from any birth date to any target date.

Currency Converter

Convert currencies instantly with real-time exchange rates and historical data support.

Your Feedback Matters

Help Us to Improve