diff --git a/src/Core__Float.res b/src/Core__Float.res
index 8781324d..a040f90b 100644
--- a/src/Core__Float.res
+++ b/src/Core__Float.res
@@ -10,9 +10,6 @@ module Constants = {
 @val external isNaN: float => bool = "isNaN"
 @val external isFinite: float => bool = "isFinite"
 @val external parseFloat: 'a => float = "parseFloat"
-// parseInt's return type is a float because it can be NaN
-@val external parseInt: 'a => float = "parseInt"
-@val external parseIntWithRadix: ('a, ~radix: int) => float = "parseInt"
 
 @send external toExponential: float => string = "toExponential"
 @send external toExponentialWithPrecision: (float, ~digits: int) => string = "toExponential"
diff --git a/src/Core__Float.resi b/src/Core__Float.resi
index cb3e835b..a35114cf 100644
--- a/src/Core__Float.resi
+++ b/src/Core__Float.resi
@@ -157,44 +157,6 @@ Float.parseFloat("error")->Float.isNaN // true
 @val
 external parseFloat: string => float = "parseFloat"
 
-/**
-`parseInt(v)` parse the given `v` and returns a float. Leading whitespace in
-`v` is ignored. Returns `NaN` if `v` can't be parsed.
-See [`parseInt`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/parseInt) on MDN.
-
-## Examples
-
-```rescript
-Float.parseInt("1.0") // 1.0
-Float.parseInt("  3.14   ") // 3.0
-Float.parseInt(3) // 3.0
-Float.parseInt("3.14some non-digit characters") // 3.0
-Float.parseInt("error")->Float.isNaN // true
-```
-*/
-@val
-external parseInt: 'a => float = "parseInt"
-
-/**
-`parseIntWithRadix(v, ~radix)` parse the given `v` and returns a float. Leading
-whitespace in this argument `v`is ignored. `radix` specifies the radix base to
-use for the formatted number. The value must be in the range [2, 36] (inclusive).
-Returns `NaN` if `v` can't be parsed and `radix` is smaller than 2 or bigger
-than 36.
-See [`parseInt`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/parseInt) on MDN.
-
-## Examples
-
-```rescript
-Float.parseInt("10.0", ~radix=2) // 2.0
-Float.parseInt("15 * 3", ~radix=10) // 15.0
-Float.parseInt("12", ~radix=13) // 15.0
-Float.parseInt("17", ~radix=40)->Float.isNaN // true
-```
-*/
-@val
-external parseIntWithRadix: ('a, ~radix: int) => float = "parseInt"
-
 /**
 `toExponential(v)` return a `string` representing the given value in exponential
 notation.
diff --git a/src/Core__Int.mjs b/src/Core__Int.mjs
index 98b0dc45..55dd2604 100644
--- a/src/Core__Int.mjs
+++ b/src/Core__Int.mjs
@@ -6,7 +6,7 @@ function fromString(radix, x) {
   if (isNaN(maybeInt) || maybeInt > 2147483647 || maybeInt < -2147483648) {
     return ;
   } else {
-    return maybeInt | 0;
+    return maybeInt;
   }
 }
 
diff --git a/src/Core__Int.res b/src/Core__Int.res
index 29172623..5b4ac076 100644
--- a/src/Core__Int.res
+++ b/src/Core__Int.res
@@ -2,7 +2,7 @@ module Constants = {
   @inline let minValue = -2147483648
   @inline let maxValue = 2147483647
 }
-
+@val external isNaN: int => bool = "isNaN"
 @send external toExponential: int => string = "toExponential"
 @send external toExponentialWithPrecision: (int, ~digits: int) => string = "toExponential"
 
@@ -19,18 +19,20 @@ module Constants = {
 external toFloat: int => float = "%identity"
 external fromFloat: float => int = "%intoffloat"
 
+@val external parseInt: 'a => int = "parseInt"
+@val external parseIntWithRadix: ('a, ~radix: int) => int = "parseInt"
+
 let fromString = (~radix=?, x) => {
   let maybeInt = switch radix {
-  | Some(radix) => Core__Float.parseIntWithRadix(x, ~radix)
-  | None => Core__Float.parseInt(x)
+  | Some(radix) => parseIntWithRadix(x, ~radix)
+  | None => parseInt(x)
   }
-  if Core__Float.isNaN(maybeInt) {
+  if isNaN(maybeInt) {
     None
-  } else if maybeInt > Constants.maxValue->toFloat || maybeInt < Constants.minValue->toFloat {
+  } else if maybeInt > Constants.maxValue || maybeInt < Constants.minValue {
     None
   } else {
-    let asInt = fromFloat(maybeInt)
-    Some(asInt)
+    Some(maybeInt)
   }
 }
 
diff --git a/src/Core__Int.resi b/src/Core__Int.resi
index 68498f18..43662b76 100644
--- a/src/Core__Int.resi
+++ b/src/Core__Int.resi
@@ -56,6 +56,20 @@ module Constants: {
   let maxValue: int
 }
 
+/**
+`isNaN(v)` tests if the given `v` is `NaN`.
+See [`NaN`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/NaN) on MDN.
+
+## Examples
+
+```rescript
+Int.isNaN(3) // false
+Int.isNaN(Int.parseInt("error")) // true
+```
+*/
+@val
+external isNaN: int => bool = "isNaN"
+
 /**
 `toExponential(n)` return a `string` representing the given value in exponential
 notation.
@@ -244,6 +258,44 @@ Int.fromFloat(0.9999) == 0
 */
 external fromFloat: float => int = "%intoffloat"
 
+/**
+`parseInt(v)` parse the given `v` and returns an int. Leading whitespace in
+`v` is ignored. Returns `NaN` if `v` can't be parsed.
+See [`parseInt`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/parseInt) on MDN.
+
+## Examples
+
+```rescript
+Int.parseInt("1.0") // 1
+Int.parseInt("  3.14   ") // 3
+Int.parseInt(3) // 3
+Int.parseInt("3.14some non-digit characters") // 3
+Int.parseInt("error")->Int.isNaN // true
+```
+*/
+@val
+external parseInt: 'a => int = "parseInt"
+
+/**
+`parseIntWithRadix(v, ~radix)` parse the given `v` and returns an int. Leading
+whitespace in this argument `v` is ignored. `radix` specifies the radix base to
+use for the formatted number. The value must be in the range [2, 36] (inclusive).
+Returns `NaN` if `v` can't be parsed and `radix` is smaller than 2 or bigger
+than 36.
+See [`parseInt`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/parseInt) on MDN.
+
+## Examples
+
+```rescript
+Int.parseInt("10.0", ~radix=2) // 2
+Int.parseInt("15 * 3", ~radix=10) // 15
+Int.parseInt("12", ~radix=13) // 15
+Int.parseInt("17", ~radix=40)->Int.isNaN // true
+```
+*/
+@val
+external parseIntWithRadix: ('a, ~radix: int) => int = "parseInt"
+
 /**
 `fromString(~radix?, str)` return an `option<int>` representing the given value
 `str`. `~radix` specifies the radix base to use for the formatted number.
diff --git a/test/TestSuite.mjs b/test/TestSuite.mjs
index 64ebfbc1..f3e3bfee 100644
--- a/test/TestSuite.mjs
+++ b/test/TestSuite.mjs
@@ -1,7 +1,7 @@
 // Generated by ReScript, PLEASE EDIT WITH CARE
 
-import * as ErrorTests from "./ErrorTests.mjs";
 import * as ArrayTests from "./ArrayTests.mjs";
+import * as ErrorTests from "./ErrorTests.mjs";
 import * as PromiseTest from "./PromiseTest.mjs";
 
 var TestError = PromiseTest.TestError;