Technology & Computing
RSA Key Length Security Strength Calculator
Estimate the symmetric-equivalent security strength and relative computational cost of an RSA key length.
Your inputs
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Equivalent symmetric security
112 bits
RSA modulus length
2,048 bits
Relative sign/keygen cost vs 2048-bit
1 x
Considered secure until (rule of thumb)
2,025
1024-bit RSA is considered breakable by well-resourced attackers; 2048-bit is the current minimum, 3072-bit+ recommended for long-term security.
Formula and working
Approximate NIST SP 800-57 mapping of RSA modulus bits to equivalent symmetric security bits
- 1
Collect the inputs
RSA key length = 2,048
- 2
Apply the formula
Approximate NIST SP 800-57 mapping of RSA modulus bits to equivalent symmetric security bits
- 3
Result
Equivalent symmetric security = 112 bits
Frequently asked questions
Important limitation
This is an educational estimate based only on the values and formula shown. Verify current rates, rules, units, and professional standards before relying on the result. It is not personalized financial or investment advice.
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