diff --git a/src/index.test.ts b/src/index.test.ts
index 5035ab9..07a4170 100644
--- a/src/index.test.ts
+++ b/src/index.test.ts
@@ -327,6 +327,13 @@ describe('ms(number)', () => {
 
     expect(ms(-234234234)).toBe('-3d');
   });
+
+  it('should roundtrip format/parse for large numbers', () => {
+    const formatted = ms(Number.MAX_VALUE);
+    expect(typeof formatted).toBe('string');
+    const parsed = ms(formatted as `${number}`);
+    expect(parsed).not.toBeNaN();
+  });
 });
 
 // invalid inputs
diff --git a/src/index.ts b/src/index.ts
index d50e3c7..0796c11 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -75,7 +75,7 @@ export function parse(str: string): number {
     );
   }
   const match =
-    /^(?<value>-?\d*\.?\d+) *(?<unit>milliseconds?|msecs?|ms|seconds?|secs?|s|minutes?|mins?|m|hours?|hrs?|h|days?|d|weeks?|w|months?|mo|years?|yrs?|y)?$/i.exec(
+    /^(?<value>-?(?:\d*\.?\d+)(?:e[+-]?\d+)?) *(?<unit>milliseconds?|msecs?|ms|seconds?|secs?|s|minutes?|mins?|m|hours?|hrs?|h|days?|d|weeks?|w|months?|mo|years?|yrs?|y)?$/i.exec(
       str,
     );
 
diff --git a/src/parse.test.ts b/src/parse.test.ts
index 9182411..e904807 100644
--- a/src/parse.test.ts
+++ b/src/parse.test.ts
@@ -78,6 +78,15 @@ describe('parse(string)', () => {
   it('should work with negative decimals starting with "."', () => {
     expect(parse('-.5h')).toBe(-1800000);
   });
+
+  it('should work with scientific notation (roundtrip from format)', () => {
+    expect(parse('5.696545792019405e+297y')).not.toBeNaN();
+    expect(parse('1e3ms')).toBe(1000);
+    expect(parse('1.5e2s')).toBe(150000);
+    expect(parse('-1e3ms')).toBe(-1000);
+    expect(parse('1E3ms')).toBe(1000);
+    expect(parse('1e+3ms')).toBe(1000);
+  });
 });
 
 // long strings