@@ -744,7 +744,12 @@ protected Value createValue(GraphqlParser.ValueContext ctx) {
             addCommonData(intValue, ctx);
             return captureRuleContext(intValue.build(), ctx);
         } else if (ctx.FloatValue() != null) {
-            FloatValue.Builder floatValue = FloatValue.newFloatValue().value(new BigDecimal(ctx.FloatValue().getText()));
+            FloatValue.Builder floatValue;
+            try {
+                floatValue = FloatValue.newFloatValue().value(new BigDecimal(ctx.FloatValue().getText()));
+            } catch (NumberFormatException e) {
+                throw new InvalidSyntaxException("Invalid floating point value", null, ctx.FloatValue().getText(), null, e);
+            }
             addCommonData(floatValue, ctx);
             return captureRuleContext(floatValue.build(), ctx);
         } else if (ctx.BooleanValue() != null) {
 
@@ -1009,6 +1009,22 @@ triple3 : """edge cases \\""" "" " \\"" \\" edge cases"""
         '1.2e3e'  | _
     }
 
+    @Unroll
+    def "float literal with out-of-range exponent #value is a syntax error"() {
+        when:
+        Parser.parse(input)
+
+        then:
+        def e = thrown(InvalidSyntaxException)
+        e.message.contains("Invalid floating point value")
+
+        where:
+        input                                          | value
+        'query($x: Float = 1.0e9999999999) {foo}'      | '1.0e9999999999 (variable default value)'
+        'query($x: Float = [1.0e9999999999]) {foo}'    | '1.0e9999999999 (nested in list default)'
+        '{foo(arg: 1.0e9999999999)}'                   | '1.0e9999999999 (argument value)'
+    }
+
     @Unroll
     def 'parse ast field definition #valueLiteral'() {
         expect: