The word decidable may refer to:

• Decidable language
• Decidability (logic) for the equivalent in mathematical logic
• Decidable problem and Undecidable problem
• Gödel's incompleteness theorem, a theorem on the undecidability of languages consisting of "true statements" in mathematical logic.
• Recursive set, a "decidable set" in recursion theory

• Decision problem
• List of undecidable problems
• Decision (disambiguation)
• Decide (disambiguation)