Truth tables, tableaux and proofs for propositional logic
Type a formula or an argument once, then open it in any tool. Everything runs in your browser, and none of it needs an account.
What are you entering?
Premises separated by commas, then ∴ and the conclusion, as in P → Q, P ∴ Q.
From the keyboard
- ~¬
- &∧
- v∨
- ->→
- <->↔
- #⊥
- :.∴
Tools
- Truth tablesFill in full or short truth tables and test validity, equivalence and consistency.
- TableauxGrow a tableau branch by branch and read countermodels off the open branches.
- ProofsWrite Fitch-style natural deduction proofs, checked line by line, with hints when you're stuck.
- SyntaxSee a formula's syntax tree, its main connective and every subformula.
- Normal formsRewrite a formula into conjunctive or disjunctive normal form, one step at a time.
- ExercisesPractise with exercise sets in the style of forall x, or generate fresh problems.