diff --git a/internal/prepare/prepare_gender.go b/internal/prepare/prepare_gender.go
new file mode 100644
index 00000000..f67e2927
--- /dev/null
+++ b/internal/prepare/prepare_gender.go
@@ -0,0 +1,21 @@
+package prepare
+
+import (
+	"strings"
+
+	"github.com/moov-io/watchman/pkg/search"
+)
+
+func NormalizeGender(input string) search.Gender {
+	v := strings.ToLower(strings.TrimSpace(input))
+
+	switch v {
+	case "m", "male", "man", "guy":
+		return search.GenderMale
+
+	case "f", "female", "woman", "gal", "girl":
+		return search.GenderFemale
+	}
+
+	return search.GenderUnknown
+}
diff --git a/internal/prepare/prepare_gender_test.go b/internal/prepare/prepare_gender_test.go
new file mode 100644
index 00000000..8a060659
--- /dev/null
+++ b/internal/prepare/prepare_gender_test.go
@@ -0,0 +1,29 @@
+package prepare
+
+import (
+	"testing"
+
+	"github.com/moov-io/watchman/pkg/search"
+
+	"github.com/stretchr/testify/require"
+)
+
+func TestPrepare_NormalizeGender(t *testing.T) {
+	cases := []struct {
+		input    string
+		expected search.Gender
+	}{
+		{"M", search.GenderMale},
+		{"Male", search.GenderMale},
+		{"guy", search.GenderMale},
+		{"F", search.GenderFemale},
+		{"FEMALE", search.GenderFemale},
+		{"Girl", search.GenderFemale},
+	}
+	for _, tc := range cases {
+		t.Run(tc.input, func(t *testing.T) {
+			got := NormalizeGender(tc.input)
+			require.Equal(t, tc.expected, got)
+		})
+	}
+}
diff --git a/internal/search/api_search.go b/internal/search/api_search.go
index b70f65e5..91d4ecc4 100644
--- a/internal/search/api_search.go
+++ b/internal/search/api_search.go
@@ -8,6 +8,7 @@ import (
 	"strings"
 	"time"
 
+	"github.com/moov-io/watchman/internal/prepare"
 	"github.com/moov-io/watchman/pkg/address"
 	"github.com/moov-io/watchman/pkg/search"
 
@@ -139,7 +140,7 @@ func readSearchRequest(r *http.Request) (search.Entity[search.Value], error) {
 		req.Person = &search.Person{
 			Name:      req.Name,
 			AltNames:  q["altNames"],
-			Gender:    search.Gender(strings.TrimSpace(q.Get("gender"))),
+			Gender:    prepare.NormalizeGender(q.Get("gender")),
 			BirthDate: readDate(q.Get("birthDate")),
 			DeathDate: readDate(q.Get("deathDate")),
 			Titles:    q["titles"],