diff --git a/staging/src/k8s.io/apiextensions-apiserver/pkg/apiserver/validation/formats.go b/staging/src/k8s.io/apiextensions-apiserver/pkg/apiserver/validation/formats.go
index f818010f1b7..c11f1c627a7 100644
--- a/staging/src/k8s.io/apiextensions-apiserver/pkg/apiserver/validation/formats.go
+++ b/staging/src/k8s.io/apiextensions-apiserver/pkg/apiserver/validation/formats.go
@@ -105,6 +105,22 @@ func StripUnsupportedFormatsPostProcessorForVersion(compatibilityVersion *versio
 	}
 }
 
+// GetUnrecognizedFormats returns a list of unrecognized formats found in the given schema.
+// It uses the same source of truth as StripUnsupportedFormatsPostProcessorForVersion.
+func GetUnrecognizedFormats(schema *spec.Schema, compatibilityVersion *version.Version) []string {
+	var unrecognizedFormats []string
+	if len(schema.Format) == 0 {
+		return unrecognizedFormats
+	}
+
+	normalized := strings.ReplaceAll(schema.Format, "-", "") // go-openapi default format name normalization
+	if !supportedFormatsAtVersion(compatibilityVersion).supported.Has(normalized) {
+		unrecognizedFormats = append(unrecognizedFormats, schema.Format)
+	}
+
+	return unrecognizedFormats
+}
+
 type versionedFormats struct {
 	introducedVersion *version.Version
 	formats           sets.Set[string]
diff --git a/staging/src/k8s.io/apiextensions-apiserver/pkg/apiserver/validation/formats_test.go b/staging/src/k8s.io/apiextensions-apiserver/pkg/apiserver/validation/formats_test.go
index c93a7f74d1d..7558444b218 100644
--- a/staging/src/k8s.io/apiextensions-apiserver/pkg/apiserver/validation/formats_test.go
+++ b/staging/src/k8s.io/apiextensions-apiserver/pkg/apiserver/validation/formats_test.go
@@ -138,3 +138,86 @@ func TestSupportedFormats(t *testing.T) {
 		})
 	}
 }
+
+func TestGetUnrecognizedFormats(t *testing.T) {
+	testCases := []struct {
+		name                 string
+		schema               *spec.Schema
+		compatibilityVersion *version.Version
+		expectedFormats      []string
+	}{
+		{
+			name:                 "empty format",
+			schema:               &spec.Schema{SchemaProps: spec.SchemaProps{Format: ""}},
+			compatibilityVersion: version.MajorMinor(1, 0),
+			expectedFormats:      []string{},
+		},
+		{
+			name:                 "recognized format at version 1.0",
+			schema:               &spec.Schema{SchemaProps: spec.SchemaProps{Format: "email"}},
+			compatibilityVersion: version.MajorMinor(1, 0),
+			expectedFormats:      []string{},
+		},
+		{
+			name:                 "unrecognized format at version 1.0",
+			schema:               &spec.Schema{SchemaProps: spec.SchemaProps{Format: "unknown-format"}},
+			compatibilityVersion: version.MajorMinor(1, 0),
+			expectedFormats:      []string{"unknown-format"},
+		},
+		{
+			name:                 "recognized format with normalization",
+			schema:               &spec.Schema{SchemaProps: spec.SchemaProps{Format: "k8s-short-name"}},
+			compatibilityVersion: version.MajorMinor(1, 34),
+			expectedFormats:      []string{},
+		},
+		{
+			name:                 "unrecognized format with normalization",
+			schema:               &spec.Schema{SchemaProps: spec.SchemaProps{Format: "k8s-long-name"}},
+			compatibilityVersion: version.MajorMinor(1, 33),
+			expectedFormats:      []string{"k8s-long-name"},
+		},
+		{
+			name:                 "format introduced in later version",
+			schema:               &spec.Schema{SchemaProps: spec.SchemaProps{Format: "k8s-short-name"}},
+			compatibilityVersion: version.MajorMinor(1, 0),
+			expectedFormats:      []string{"k8s-short-name"},
+		},
+		{
+			name:                 "format with dash normalization",
+			schema:               &spec.Schema{SchemaProps: spec.SchemaProps{Format: "k8sshortname"}},
+			compatibilityVersion: version.MajorMinor(1, 34),
+			expectedFormats:      []string{},
+		},
+		{
+			name:                 "recognized format at exact version",
+			schema:               &spec.Schema{SchemaProps: spec.SchemaProps{Format: "uuid"}},
+			compatibilityVersion: version.MajorMinor(1, 0),
+			expectedFormats:      []string{},
+		},
+		{
+			name:                 "recognized format at higher version",
+			schema:               &spec.Schema{SchemaProps: spec.SchemaProps{Format: "email"}},
+			compatibilityVersion: version.MajorMinor(1, 35),
+			expectedFormats:      []string{},
+		},
+	}
+
+	for _, tc := range testCases {
+		t.Run(tc.name, func(t *testing.T) {
+			got := GetUnrecognizedFormats(tc.schema, tc.compatibilityVersion)
+
+			if len(got) != len(tc.expectedFormats) {
+				t.Errorf("expected %d unrecognized formats, got %d", len(tc.expectedFormats), len(got))
+				return
+			}
+
+			// Convert to sets for comparison to handle order differences
+			gotSet := sets.New(got...)
+			expectedSet := sets.New(tc.expectedFormats...)
+
+			if !gotSet.Equal(expectedSet) {
+				t.Errorf("expected unrecognized formats %v, got %v", tc.expectedFormats, got)
+			}
+		})
+	}
+}