Logical Equivalence Checker
Test whether two propositional logic expressions produce identical truth values across all variable assignments.
Inputs
Results
Equivalent (1=Yes)
0
Matching Rows
0
How to Use This Calculator
- Enter two logical expressions using standard propositional logic notation.
- Assign truth values to each variable and evaluate both expressions.
- Review the truth table output showing both expressions' values at every input combination.
- If the truth values match for all inputs, the expressions are logically equivalent.
- Use the equivalence check to simplify complex propositions in proofs or circuit design.
How the result changes with Expression 2 (1=AND, 2=OR, 3=XOR, 4=IMPLIES, 5=NAND)
| Expression 2 (1=AND, 2=OR, 3=XOR, 4=IMPLIES, 5=NAND) | Equivalent (1=Yes) | Matching Rows |
|---|---|---|
| 1.4 | 1 | 4 |
| 2.4 | 0 | 2 |
| 3.6 | 0 | 2 |
| 4.6 | 0 | 0 |
What each input means
- Expression 1 (1=AND, 2=OR, 3=XOR, 4=IMPLIES, 5=NAND)
- Logical operation for the first expression
- Expression 2 (1=AND, 2=OR, 3=XOR, 4=IMPLIES, 5=NAND)
- Logical operation for the second expression
- Number of Variables
- Number of propositional variables shared between both expressions
How this is calculated
Worked example, using the default values
- Identify Input ParametersExpression 1 (1=AND, 2=OR, 3=XOR, 4=IMPLIES, 5=NAND) = 1, Expression 2 (1=AND, 2=OR, 3=XOR, 4=IMPLIES, 5=NAND) = 5, Number of Variables = 2 = 3 input(s) provided
- Calculate EquivalentEquivalent0 = 0
- Calculate Matching RowsMatching Rows0 = 0
- Calculate Different RowsDifferent Rows4 = 4
- Calculate Match PercentageMatch Percentage0 = 0
Engine last updated . Checked against 5 independently-derived tests — how we verify calculators.
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