diff --git a/README.md b/README.md
index 92baaef..1cb56a9 100644
--- a/README.md
+++ b/README.md
@@ -31,3 +31,21 @@ Your assistance in maintaining and improving these lists is greatly appreciated.
 ## License
 
 This project is licensed under a [Creative Commons Attribution-ShareAlike 4.0 International License(CC-BY-SA-4.0)](https://creativecommons.org/licenses/by-sa/4.0/).
+
+## Managing Domains
+
+A shell script `manage_domains.sh` is provided to help manage the domains in the `list` and `inactive` files. The script ensures that the files remain sorted and comments are not affected.
+
+### Usage
+
+To add a new domain to the list file:
+
+```sh
+./manage_domains.sh add <domain>
+```
+
+To move an inactive domain to the inactive list:
+
+```sh
+./manage_domains.sh move <domain>
+```
diff --git a/manage_domains.sh b/manage_domains.sh
new file mode 100755
index 0000000..f35c3e9
--- /dev/null
+++ b/manage_domains.sh
@@ -0,0 +1,70 @@
+#!/bin/bash
+
+export LC_ALL=C
+
+SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+
+if [ -z "$LIST_FILE" ]; then
+    LIST_FILE="${SCRIPT_DIR}/list"
+fi
+if [ -z "$INACTIVE_FILE" ]; then
+    INACTIVE_FILE="${SCRIPT_DIR}/inactive"
+fi
+
+# Validate files exist
+for file in "$LIST_FILE" "$INACTIVE_FILE"; do
+    if [[ ! -f "$file" ]]; then
+        echo "Error: Required file $file not found"
+        exit 1
+    fi
+done
+
+add_domain() {
+    local domain=$1
+    # Validate domain format
+    if ! echo "$domain" | grep -qP '^(?:[a-z0-9](?:[a-z0-9-]{0,61}[a-z0-9])?\.)+[a-z]{2,}$'; then
+        echo "Error: Invalid domain format: $domain"
+        exit 1
+    fi
+    if ! grep -q "^$domain$" "$LIST_FILE"; then
+        echo "$domain" >> "$LIST_FILE"
+        # Preserve comments at top of file
+        (grep '^#' "$LIST_FILE"; grep -v '^#' "$LIST_FILE" | sort) > "$LIST_FILE.tmp" && mv "$LIST_FILE.tmp" "$LIST_FILE"
+        echo "Domain $domain added to $LIST_FILE."
+    else
+        echo "Domain $domain already exists in $LIST_FILE."
+    fi
+}
+
+move_domain() {
+    local domain=$1
+    if grep -q "^$domain$" "$LIST_FILE"; then
+        sed -i "/^$domain$/d" "$LIST_FILE"
+        echo "$domain" >> "$INACTIVE_FILE"
+        (head -n 15 "$INACTIVE_FILE" && tail -n +16 "$INACTIVE_FILE" | sort) > "$INACTIVE_FILE.tmp" && mv "$INACTIVE_FILE.tmp" "$INACTIVE_FILE"
+        echo "Domain $domain moved to $INACTIVE_FILE."
+    else
+        echo "Domain $domain does not exist in $LIST_FILE."
+    fi
+}
+
+if [ "$#" -ne 2 ]; then
+    echo "Usage: $0 {add|move} domain"
+    exit 1
+fi
+
+command=$1
+domain=$2
+
+case $command in
+    add)
+        add_domain "$domain"
+        ;;
+    move)
+        move_domain "$domain"
+        ;;
+    *)
+        echo "Invalid command. Use 'add' to add a domain or 'move' to move a domain."
+        exit 1
+        ;;
+esac
diff --git a/tests/manage_domains_test.sh b/tests/manage_domains_test.sh
new file mode 100755
index 0000000..3be6a4a
--- /dev/null
+++ b/tests/manage_domains_test.sh
@@ -0,0 +1,108 @@
+#!/bin/bash
+set -euo pipefail
+
+failures=0
+export LC_ALL=C
+SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+
+RED='\033[0;31m'
+GREEN='\033[0;32m'
+YELLOW='\033[1;33m'
+NC='\033[0m'
+
+TEST_DIR=$(mktemp -d)
+echo -e "${YELLOW}Creating temporary test directory: $TEST_DIR${NC}"
+trap 'rm -rf "$TEST_DIR"' EXIT
+
+echo -e "${YELLOW}Copying test files to temporary directory${NC}"
+list_file="${SCRIPT_DIR}/../list"
+inactive_file="${SCRIPT_DIR}/../inactive"
+
+test_list_file="${TEST_DIR}/test_list"
+test_inactive_file="${TEST_DIR}/test_inactive"
+
+cp "$list_file" "$test_list_file"
+cp "$inactive_file" "$test_inactive_file"
+
+export LIST_FILE="$test_list_file"
+export INACTIVE_FILE="$test_inactive_file"
+
+# Test helper function
+run_test() {
+    local name="$1"
+    local code="$2"
+    if [ "$code" -eq 0 ]; then
+        echo -e "${GREEN}Test $name: PASSED${NC}"
+    else
+        echo -e "${RED}Test $name: FAILED${NC}"
+        failures=$((failures+1))
+    fi
+}
+
+# Testing: Add domain
+echo
+echo -e "${YELLOW}Testing: Add domain${NC}"
+"${SCRIPT_DIR}/../manage_domains.sh" add "newdomain.com"
+run_test "add domain" "$(grep -q "^newdomain.com$" "$test_list_file"; echo $?)"
+echo
+
+# Testing: Add invalid domain
+echo -e "${YELLOW}Testing: Add invalid domain${NC}"
+if "${SCRIPT_DIR}/../manage_domains.sh" add "invalid..domain" 2>/dev/null; then
+    run_test "reject invalid domain" 1
+else
+    run_test "reject invalid domain" 0
+fi
+echo
+
+# Testing: Move domain to inactive
+echo -e "${YELLOW}Testing: Move domain to inactive${NC}"
+"${SCRIPT_DIR}/../manage_domains.sh" move "newdomain.com"
+run_test "move domain" "$(grep -q "^newdomain.com$" "$test_inactive_file" && ! grep -q "^newdomain.com$" "$test_list_file"; echo $?)"
+echo
+
+# Testing: Move non-existent domain
+echo -e "${YELLOW}Testing: Move non-existent domain${NC}"
+if "${SCRIPT_DIR}/../manage_domains.sh" move "nonexistentdomain.com" 2>/dev/null; then
+    run_test "graceful handling of non-existent domain" "$( ! grep -q "^nonexistentdomain.com$" "$test_inactive_file"; echo $?)"
+else
+    run_test "graceful handling of non-existent domain" 1
+fi
+echo
+
+# Testing: File sorting and comment preservation
+echo -e "${YELLOW}Testing: File sorting and comment preservation${NC}"
+"${SCRIPT_DIR}/../manage_domains.sh" add "anotherdomain.com"
+"${SCRIPT_DIR}/../manage_domains.sh" move "anotherdomain.com"
+run_test "file sorting and comments" "$(diff -u <(grep -v -E '^(#|$)' "$test_list_file" | sort) <(grep -v -E '^(#|$)' "$test_list_file") && diff -u <(grep -v -E '^(#|$)' "$test_inactive_file" | sort) <(grep -v -E '^(#|$)' "$test_inactive_file"); echo $?)"
+echo
+
+# Testing: Comment preservation
+echo -e "${YELLOW}Testing: Comment preservation${NC}"
+orig_comments=$(grep '^#' "$list_file")
+new_comments=$(grep '^#' "$test_list_file")
+if [ "$orig_comments" = "$new_comments" ]; then
+    echo -e "${GREEN}Test comment preservation (active): PASSED${NC}"
+else
+    echo -e "${RED}Test comment preservation (active): FAILED${NC}"
+    failures=$((failures+1))
+fi
+
+orig_comments_inactive=$(grep '^#' "$inactive_file")
+new_comments_inactive=$(grep '^#' "$test_inactive_file")
+if [ "$orig_comments_inactive" = "$new_comments_inactive" ]; then
+    echo -e "${GREEN}Test comment preservation (inactive): PASSED${NC}"
+else
+    echo -e "${RED}Test comment preservation (inactive): FAILED${NC}"
+    failures=$((failures+1))
+fi
+
+echo
+echo -e "${YELLOW}Test summary:${NC}"
+if [ "$failures" -eq 0 ]; then
+    echo -e "${GREEN}All tests passed${NC}"
+else
+    echo -e "${RED}$failures tests failed${NC}"
+fi
+
+exit "$failures"