diff --git a/.changeset/dockerignore-ascii-digit-class.md b/.changeset/dockerignore-ascii-digit-class.md
new file mode 100644
index 0000000000..86ba6267ec
--- /dev/null
+++ b/.changeset/dockerignore-ascii-digit-class.md
@@ -0,0 +1,5 @@
+---
+"@e2b/dockerfile-utils-python": patch
+---
+
+Keep bracket class escapes in Dockerignore patterns ASCII-only, matching Moby and the JavaScript utility. Non-ASCII decimal digits are no longer excluded by a pattern such as `[\d]`, and non-ASCII spaces by a pattern such as `[\s]`.
diff --git a/.changeset/dockerignore-ascii-whitespace-class.md b/.changeset/dockerignore-ascii-whitespace-class.md
new file mode 100644
index 0000000000..a8c853c22b
--- /dev/null
+++ b/.changeset/dockerignore-ascii-whitespace-class.md
@@ -0,0 +1,5 @@
+---
+"@e2b/dockerfile-utils": patch
+---
+
+Keep bracket whitespace classes in Dockerignore patterns ASCII-only, matching Moby and the Python utility. Non-ASCII spaces such as U+00A0 are no longer matched by a pattern such as `[\s]`.
diff --git a/packages/dockerfile-utils-js/src/dockerignore.ts b/packages/dockerfile-utils-js/src/dockerignore.ts
index 6d5ae226d6..36581e9b4d 100644
--- a/packages/dockerfile-utils-js/src/dockerignore.ts
+++ b/packages/dockerfile-utils-js/src/dockerignore.ts
@@ -25,14 +25,23 @@ function escapeRegex(ch: string): string {
 }
 
 // Escapes that keep their regex meaning in a bracket expression, like in Python
-const CLASS_ESCAPES = new Set('dDsSwWfnrtv')
+const CLASS_ESCAPES = new Set('dDwWfnrtv')
+// ASCII-only whitespace like Moby, as JS `\s` also matches Unicode spaces
+const CLASS_WHITESPACE_ESCAPES: Record<string, string> = {
+  s: '\\t-\\r ',
+  S: '\\u{0}-\\u{8}\\u{e}-\\u{1f}\\u{21}-\\u{10ffff}',
+}
 const CLASS_CONTROL_ESCAPES: Record<string, string> = { a: '\\x07', b: '\\x08' }
 const CLASS_HEX_ESCAPE_LENGTHS: Record<string, number> = { x: 2, u: 4, U: 8 }
 // Characters that must stay escaped in a bracket expression with the `u` flag
 const CLASS_SYNTAX_CHARS = new Set('^$\\.*+?()[]{}|/-')
 
 // Make a bracket expression body valid with the regex `u` flag
-function translateClass(body: string, backslashIsEscape: boolean): string {
+function translateClass(
+  body: string,
+  backslashIsEscape: boolean,
+  unicodeWhitespace = false
+): string {
   let cls = ''
   let i = 0
   while (i < body.length) {
@@ -45,6 +54,8 @@ function translateClass(body: string, backslashIsEscape: boolean): string {
       const next = body[i++]
       if (CLASS_ESCAPES.has(next)) {
         cls += '\\' + next
+      } else if (next in CLASS_WHITESPACE_ESCAPES) {
+        cls += unicodeWhitespace ? '\\' + next : CLASS_WHITESPACE_ESCAPES[next]
       } else if (next in CLASS_CONTROL_ESCAPES) {
         cls += CLASS_CONTROL_ESCAPES[next]
       } else if (next in CLASS_HEX_ESCAPE_LENGTHS) {
@@ -78,6 +89,10 @@ function translateClass(body: string, backslashIsEscape: boolean): string {
       }
     }
   }
+  if (!unicodeWhitespace) {
+    // Reject ranges such as `[\s-x]` that the expanded set would allow
+    new RegExp('[' + translateClass(body, backslashIsEscape, true) + ']', 'u')
+  }
   return cls
 }
 
diff --git a/packages/dockerfile-utils-js/tests/dockerignore.test.ts b/packages/dockerfile-utils-js/tests/dockerignore.test.ts
index c778e6025f..fc7a382ca9 100644
--- a/packages/dockerfile-utils-js/tests/dockerignore.test.ts
+++ b/packages/dockerfile-utils-js/tests/dockerignore.test.ts
@@ -84,3 +84,20 @@ test('rejects invalid patterns with a plain Error', () => {
     "Invalid ignore pattern '[\\q]'"
   )
 })
+
+test.each([
+  ['[\\d]', '5', true],
+  ['[\\d]', '\u0661', false],
+  ['[\\d]', 'd', false],
+  ['[\\s]', ' ', true],
+  ['[\\s]', '\u00a0', false],
+  ['[\\S]', '\u00a0', true],
+  ['[\\S]', '\t', false],
+])('class %s matches %j: %s', (pattern, path, excluded) => {
+  assert.strictEqual(new PatternMatcher([pattern]).matches(path), excluded)
+})
+
+test('rejects ranges with a whitespace class escape', () => {
+  assert.throws(() => new PatternMatcher(['[\\s-x]']), Error)
+  assert.throws(() => new PatternMatcher(['[a-\\S]']), Error)
+})
diff --git a/packages/dockerfile-utils-python/e2b_dockerfile_utils/dockerignore.py b/packages/dockerfile-utils-python/e2b_dockerfile_utils/dockerignore.py
index 18e6d7448f..9353ffd4f5 100644
--- a/packages/dockerfile-utils-python/e2b_dockerfile_utils/dockerignore.py
+++ b/packages/dockerfile-utils-python/e2b_dockerfile_utils/dockerignore.py
@@ -144,7 +144,7 @@ def _compile(pattern: str, backslash_is_escape: bool) -> Callable[[str], bool]:
         return lambda path: path.endswith(suffix) or (
             suffix.startswith("/") and path == suffix[1:]
         )
-    compiled = re.compile(regex + r"\Z")
+    compiled = re.compile(regex + r"\Z", flags=re.ASCII)
     return lambda path: compiled.match(path) is not None
 
 
diff --git a/packages/dockerfile-utils-python/tests/test_dockerignore.py b/packages/dockerfile-utils-python/tests/test_dockerignore.py
index 4bed4766a3..5de2d1e79f 100644
--- a/packages/dockerfile-utils-python/tests/test_dockerignore.py
+++ b/packages/dockerfile-utils-python/tests/test_dockerignore.py
@@ -72,3 +72,26 @@ def test_rejects_invalid_patterns_with_value_error():
         PatternMatcher(["[abc"])
     with pytest.raises(ValueError, match=r"Invalid ignore pattern '\[\\q\]'"):
         PatternMatcher(["[\\q]"])
+
+
+@pytest.mark.parametrize(
+    ("pattern", "path", "excluded"),
+    [
+        (r"[\d]", "5", True),
+        (r"[\d]", "\u0661", False),
+        (r"[\d]", "d", False),
+        (r"[\s]", " ", True),
+        (r"[\s]", "\u00a0", False),
+        (r"[\S]", "\u00a0", True),
+        (r"[\S]", "\t", False),
+    ],
+)
+def test_class_escapes_are_ascii_only(pattern, path, excluded):
+    assert PatternMatcher([pattern]).matches(path) is excluded
+
+
+def test_rejects_ranges_with_a_whitespace_class_escape():
+    with pytest.raises(ValueError):
+        PatternMatcher([r"[\s-x]"])
+    with pytest.raises(ValueError):
+        PatternMatcher([r"[a-\S]"])