diff --git a/src/parser/grammars/grammar.pegjs b/src/parser/grammars/grammar.pegjs
index 52e0fc1d..5099e652 100644
--- a/src/parser/grammars/grammar.pegjs
+++ b/src/parser/grammars/grammar.pegjs
@@ -197,6 +197,13 @@ Number
 
 Operator
  = "**" { return "^" } / "*" / "^" / "%" / "/" / "+" / "-"
+ / "?" _ expr:Expression _ ":" {
+   return [
+     '?',
+     ...expr,
+     ":",
+   ];
+ }
 
 
 _ "whitespace"
diff --git a/tests/parser/Parser.test.js b/tests/parser/Parser.test.js
index f0aca376..5d39fdbc 100644
--- a/tests/parser/Parser.test.js
+++ b/tests/parser/Parser.test.js
@@ -1743,5 +1743,19 @@ describe('Parser', () => {
         expect(parsed[2]).toBe(0);
       });
     });
+    describe('Conditional Operator', () => {
+      test('roll `1?5:0', () => {
+        const parsed = Parser.parse('1?5:0');
+
+        expect(parsed).toBeInstanceOf(Array);
+        expect(parsed).toHaveLength(5);
+
+        expect(parsed[0]).toBe(1);
+        expect(parsed[1]).toEqual('?');
+        expect(parsed[2]).toBe(5);
+        expect(parsed[3]).toEqual(':');
+        expect(parsed[4]).toBe(0);
+      });
+    });
   });
 });
diff --git a/tests/rolling.test.js b/tests/rolling.test.js
index 87456d32..1ea055ee 100644
--- a/tests/rolling.test.js
+++ b/tests/rolling.test.js
@@ -399,6 +399,34 @@ describe('Rolling', () => {
       // remove the spy
       spy.mockRestore();
     });
+
+    test('roll `(d6>3)?1:0', () => {
+      const rolls = new RollResults([4]);
+      const spy = jest.spyOn(StandardDice.prototype, 'roll')
+        .mockImplementationOnce(() => rolls);
+      const roll = roller.roll('(d6>3)?1:0');
+
+      expect(roll).toBeInstanceOf(DiceRoll);
+      expect(roll.notation).toEqual('(d6>3)?1:0');
+
+      expect(roll.rolls).toHaveLength(7);
+      expect(roll.rolls[0]).toEqual('(');
+      expect(roll.rolls[1]).toEqual(rolls);
+      expect(roll.rolls[2]).toEqual(')');
+      expect(roll.rolls[3]).toEqual('?');
+      expect(roll.rolls[4]).toBe(1);
+      expect(roll.rolls[5]).toEqual(':');
+      expect(roll.rolls[6]).toBe(0);
+
+      expect(roll.total).toBe(1);
+      expect(roll.output).toEqual('(d6>3)?1:0: ([4])?1:0 = 1');
+      expect(roll.minTotal).toEqual(0);
+      expect(roll.maxTotal).toEqual(1);
+      expect(roll.averageTotal).toEqual(0.5);
+
+      // remove the spy
+      spy.mockRestore();
+    });
   });
 
   describe('Group rolls', () => {