A/B Testing Encryption Strength Calculator Examples
Worked examples show how effective security bits and attack rate change an encryption key-search comparison.
These examples use the calculator's simplified exhaustive-search model. They illustrate relative key-search effort and target margins, not complete real-world security evaluations.
112-bit versus 128-bit configuration
Comparing an older 112-bit effective-strength design with a 128-bit alternative at 1 trillion keys per second.
Input Summary
Configuration A
112 effective bits
Configuration B
128 effective bits
Attack rate
1,000,000,000,000 keys per second
Security target
128 bits
Calculation Breakdown
- 1Bit difference128 - 11216 bits
- 2Relative multiplier2^1665,536×
- 3A average brute-force time2^111 / 10^12 / 31,557,600approximately 8.23 × 10^13 years
- 4B average brute-force time2^127 / 10^12 / 31,557,600approximately 5.39 × 10^18 years
- 5Target comparison112 - 128; 128 - 128A: -16 bits; B: 0 bits
Result Summary
Target comparison
A: -16 bits; B: 0 bits
A/B Testing Encryption Strength Calculator
Configuration B has a 65,536× larger estimated key-search space and meets the 128-bit target.
128-bit versus 192-bit configuration
Comparing two configurations at an assumed rate of 1 trillion candidate keys per second.
Input Summary
Configuration A
128 effective bits
Configuration B
192 effective bits
Attack rate
1,000,000,000,000 keys per second
Security target
128 bits
Calculation Breakdown
- 1Bit difference192 - 12864 bits
- 2Relative multiplier2^64approximately 1.84 × 10^19×
- 3A average brute-force time2^127 / 10^12 / 31,557,600approximately 5.39 × 10^18 years
- 4B average brute-force time2^191 / 10^12 / 31,557,600approximately 9.95 × 10^37 years
- 5Target margin for B192 - 128+64 bits
Result Summary
Target margin for B
+64 bits
A/B Testing Encryption Strength Calculator
Configuration B has an estimated key-search space about 1.84 × 10^19 times larger than A.
Target-focused comparison at a lower attack rate
Comparing 120-bit and 128-bit effective strength using an assumed rate of 1 billion keys per second.
Input Summary
Configuration A
120 effective bits
Configuration B
128 effective bits
Attack rate
1,000,000,000 keys per second
Security target
128 bits
Calculation Breakdown
- 1Bit difference128 - 1208 bits
- 2Relative multiplier2^8256×
- 3A average brute-force time2^119 / 10^9 / 31,557,600approximately 2.05 × 10^19 years
- 4B average brute-force time2^127 / 10^9 / 31,557,600approximately 5.39 × 10^21 years
- 5Target gaps120 - 128; 128 - 128A: -8 bits; B: 0 bits
Result Summary
Target gaps
A: -8 bits; B: 0 bits
A/B Testing Encryption Strength Calculator
Configuration B meets the target and has a 256× estimated key-search advantage over A.
How to Read Your Results
A multiplier above 1 means Configuration B has greater estimated exhaustive-search resistance than A.
A positive bit difference means B is stronger in this key-search model; a negative value means A is stronger.
Brute-force years are average mathematical estimates based entirely on the selected attack rate.
Target gaps are measured in bits, not percentages or elapsed time.
Compare results only when the entered effective-bit values reflect comparable attack models.
Assumptions & Important Notes
- Each example assumes exhaustive key search and a uniform distribution of possible keys.
- Time calculations use half the theoretical key space as average work.
- The attack rate is constant and applies equally to both configurations.
- Examples ignore non-key-search attacks and implementation risks.
Related Examples
Frequently Asked Questions
Why can two examples use different attack rates?
The attack rate is a scenario input. It changes estimated time but does not change the bit difference or the B-to-A keyspace multiplier.
Does a 256× multiplier mean B is 256 times safer overall?
No. It means B has 256 times the modeled exhaustive key-search space. Overall security depends on other factors.
Can I compare AES configurations using these examples?
You can compare effective key-search strengths if the values are appropriate for the specific implementations and threat model, but the result is not a full implementation review.
Why are the time estimates so large?
Key spaces grow exponentially with bits, while the assumed attack rate grows linearly in the calculation.
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