diff --git a/src/input/input_json.rs b/src/input/input_json.rs
index cd4ac919c..dde73cf65 100644
--- a/src/input/input_json.rs
+++ b/src/input/input_json.rs
@@ -370,10 +370,7 @@ impl<'a> Input<'a> for String {
     }
 
     fn validate_int(&'a self, _strict: bool) -> ValResult<ValidationMatch<EitherInt<'a>>> {
-        match self.parse() {
-            Ok(i) => Ok(ValidationMatch::lax(EitherInt::I64(i))),
-            Err(_) => Err(ValError::new(ErrorTypeDefaults::IntParsing, self)),
-        }
+        str_as_int(self, self).map(ValidationMatch::lax)
     }
 
     fn validate_float(&'a self, _strict: bool) -> ValResult<ValidationMatch<EitherFloat<'a>>> {
diff --git a/src/input/input_string.rs b/src/input/input_string.rs
index cd5931b24..f6c33d784 100644
--- a/src/input/input_string.rs
+++ b/src/input/input_string.rs
@@ -11,7 +11,7 @@ use crate::validators::decimal::create_decimal;
 use super::datetime::{
     bytes_as_date, bytes_as_datetime, bytes_as_time, bytes_as_timedelta, EitherDate, EitherDateTime, EitherTime,
 };
-use super::shared::{str_as_bool, str_as_float};
+use super::shared::{str_as_bool, str_as_float, str_as_int};
 use super::{
     BorrowInput, EitherBytes, EitherFloat, EitherInt, EitherString, EitherTimedelta, GenericArguments, GenericIterable,
     GenericIterator, GenericMapping, Input, ValidationMatch,
@@ -112,10 +112,7 @@ impl<'a> Input<'a> for StringMapping<'a> {
 
     fn validate_int(&'a self, _strict: bool) -> ValResult<ValidationMatch<EitherInt<'a>>> {
         match self {
-            Self::String(s) => match py_string_str(s)?.parse() {
-                Ok(i) => Ok(ValidationMatch::strict(EitherInt::I64(i))),
-                Err(_) => Err(ValError::new(ErrorTypeDefaults::IntParsing, self)),
-            },
+            Self::String(s) => str_as_int(self, py_string_str(s)?).map(ValidationMatch::strict),
             Self::Mapping(_) => Err(ValError::new(ErrorTypeDefaults::IntType, self)),
         }
     }
diff --git a/tests/validators/test_int.py b/tests/validators/test_int.py
index 24928718d..c5ccd7957 100644
--- a/tests/validators/test_int.py
+++ b/tests/validators/test_int.py
@@ -504,3 +504,11 @@ def test_allow_inf_nan_false_json() -> None:
         v.validate_json('Infinity')
     with pytest.raises(ValidationError, match=r'Input should be a finite number \[type=finite_number'):
         v.validate_json('-Infinity')
+
+
+def test_json_big_int_key():
+    v = SchemaValidator({'type': 'dict', 'keys_schema': {'type': 'int'}, 'values_schema': {'type': 'str'}})
+    big_integer = 1433352099889938534014333520998899385340
+    assert v.validate_python({big_integer: 'x'}) == {big_integer: 'x'}
+    assert v.validate_json('{"' + str(big_integer) + '": "x"}') == {big_integer: 'x'}
+    assert v.validate_strings({str(big_integer): 'x'}) == {big_integer: 'x'}