diff --git a/README.md b/README.md
index 0e4d7d7..bc62a7e 100644
--- a/README.md
+++ b/README.md
@@ -119,7 +119,7 @@ lowerFirst("Hello world!");
 
 ### `splitByCase(str, splitters?)`
 
-- Splits string by the splitters provided (default: `['-', '_', '/', '.']`)
+- Splits string by the splitters provided (default: `['-', '_', '/', '.', ' ']`)
 - Splits when case changes from lower to upper or upper to lower
 - Ignores numbers for case changes
 - Case is preserved in returned value
diff --git a/src/index.ts b/src/index.ts
index f1983fd..ebe61f9 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -10,7 +10,7 @@ import type {
 } from "./types";
 
 const NUMBER_CHAR_RE = /\d/;
-const STR_SPLITTERS = ["-", "_", "/", "."] as const;
+const STR_SPLITTERS_RE = /[\s./_-]/
 
 export function isUppercase(char = ""): boolean | undefined {
   if (NUMBER_CHAR_RE.test(char)) {
@@ -28,7 +28,6 @@ export function splitByCase<
   T extends string,
   Separator extends readonly string[],
 >(str: T, separators?: Separator) {
-  const splitters = separators ?? STR_SPLITTERS;
   const parts: string[] = [];
 
   if (!str || typeof str !== "string") {
@@ -42,7 +41,7 @@ export function splitByCase<
 
   for (const char of str) {
     // Splitter
-    const isSplitter = (splitters as unknown as string).includes(char);
+    const isSplitter = Array.isArray(separators) ? separators.includes(char) : STR_SPLITTERS_RE.test(char);
     if (isSplitter === true) {
       parts.push(buff);
       buff = "";
diff --git a/src/types.ts b/src/types.ts
index 9e7f1dd..2a294bb 100644
--- a/src/types.ts
+++ b/src/types.ts
@@ -1,4 +1,32 @@
-type Splitter = "-" | "_" | "/" | ".";
+type Whitespace =
+  | "\u{9}" // '\t'
+  | "\u{A}" // '\n'
+  | "\u{B}" // '\v'
+  | "\u{C}" // '\f'
+  | "\u{D}" // '\r'
+  | "\u{20}" // ' '
+  | "\u{85}"
+  | "\u{A0}"
+  | "\u{1680}"
+  | "\u{2000}"
+  | "\u{2001}"
+  | "\u{2002}"
+  | "\u{2003}"
+  | "\u{2004}"
+  | "\u{2005}"
+  | "\u{2006}"
+  | "\u{2007}"
+  | "\u{2008}"
+  | "\u{2009}"
+  | "\u{200A}"
+  | "\u{2028}"
+  | "\u{2029}"
+  | "\u{202F}"
+  | "\u{205F}"
+  | "\u{3000}"
+  | "\u{FEFF}";
+
+type Splitter = "-" | "_" | "/" | "." | Whitespace;
 type FirstOfString<S extends string> = S extends `${infer F}${string}`
   ? F
   : never;
@@ -164,4 +192,4 @@ export type TrainCase<
 export type FlatCase<
   T extends string | readonly string[],
   Joiner extends string = "",
-> = JoinByCase<T, Joiner>;
+> = JoinByCase<T, Joiner>;
\ No newline at end of file
diff --git a/test/scule.test.ts b/test/scule.test.ts
index bd5ec3b..a26e6d1 100644
--- a/test/scule.test.ts
+++ b/test/scule.test.ts
@@ -19,11 +19,16 @@ describe("splitByCase", () => {
     ["fooBar", ["foo", "Bar"]],
     ["FooBarBaz", ["Foo", "Bar", "Baz"]],
     ["FooBARb", ["Foo", "BA", "Rb"]],
-    ["foo_bar-baz/qux", ["foo", "bar", "baz", "qux"]],
+    ["foo_bar-baz/qux quux", ["foo", "bar", "baz", "qux", "quux"]],
     ["foo--bar-Baz", ["foo", "", "bar", "Baz"]],
     ["FOO_BAR", ["FOO", "BAR"]],
     ["foo123-bar", ["foo123", "bar"]],
     ["FOOBar", ["FOO", "Bar"]],
+    ["FOO BAR", ["FOO", "BAR"]],
+    ["foO BAR", ["fo", "O", "BAR"]],
+    ["Foo BAR", ["Foo", "BAR"]],
+    ["Foo bAR", ["Foo", "b", "AR"]],
+    ["FOO Bar", ["FOO", "Bar"]],
     ["ALink", ["A", "Link"]],
     // with custom splitters
     [
diff --git a/test/types.test-d.ts b/test/types.test-d.ts
index bd722b1..0d8588d 100644
--- a/test/types.test-d.ts
+++ b/test/types.test-d.ts
@@ -22,6 +22,11 @@ describe("SplitByCase", () => {
     assertType<SplitByCase<"FOOBar">>(["FOO", "Bar"]);
     assertType<SplitByCase<"ALink">>(["A", "Link"]);
     assertType<SplitByCase<"FOO_BAR">>(["FOO", "BAR"]);
+    assertType<SplitByCase<"FOO BAR">>(["FOO", "BAR"]);
+    assertType<SplitByCase<"foO BAR">>(["fo", "O", "BAR"]);
+    assertType<SplitByCase<"Foo BAR">>(["Foo", "BAR"]);
+    assertType<SplitByCase<"Foo bAR">>(["Foo", "b", "AR"]);
+    assertType<SplitByCase<"FOO Bar">>(["FOO", "Bar"]);
   });
 
   test("custom splitters", () => {