diff --git a/helpmehelpapplication/src/main/java/ntnu/systemutvikling/team6/service/APIToDatabaseService.java b/helpmehelpapplication/src/main/java/ntnu/systemutvikling/team6/service/APIToDatabaseService.java
index e62db7a..9e73c5c 100644
--- a/helpmehelpapplication/src/main/java/ntnu/systemutvikling/team6/service/APIToDatabaseService.java
+++ b/helpmehelpapplication/src/main/java/ntnu/systemutvikling/team6/service/APIToDatabaseService.java
@@ -2,6 +2,7 @@
 
 import java.sql.Connection;
 import java.sql.PreparedStatement;
+import java.sql.ResultSet;
 import java.sql.SQLException;
 import java.util.List;
 import java.util.UUID;
@@ -38,8 +39,7 @@ public void addAPIDataToTable(List<Charity> charities) {
     Connection conn = null;
     try {
       conn = connection.getMySqlConnection();
-      conn.setAutoCommit(
-          false);
+      conn.setAutoCommit(false);
 
       String sql1 =
           """
@@ -63,8 +63,21 @@ INSERT INTO CharityVanity (UUID_charity, charity_name, charity_link, description
                 logoBlob = VALUES(logoBlob);
         """;
 
+      String sql3 = "INSERT IGNORE INTO Categories (category) VALUES (?)";
+
+      String sql4 = "SELECT category_id FROM Categories WHERE category = ?";
+
+      String sql5 =
+          """
+        INSERT IGNORE INTO Charity_Categories (Categories_category_id, Charities_UUID_charities)
+        VALUES (?, ?)
+        """;
+
       try (PreparedStatement ps1 = conn.prepareStatement(sql1);
-          PreparedStatement ps2 = conn.prepareStatement(sql2)) {
+          PreparedStatement ps2 = conn.prepareStatement(sql2);
+          PreparedStatement ps3 = conn.prepareStatement(sql3);
+          PreparedStatement ps4 = conn.prepareStatement(sql4);
+          PreparedStatement ps5 = conn.prepareStatement(sql5)) {
 
         for (Charity charity : charities) {
           String uuid;
@@ -94,13 +107,39 @@ INSERT INTO CharityVanity (UUID_charity, charity_name, charity_link, description
           ps2.setString(6, charity.getKeyValues());
           ps2.setBytes(7, charity.getLogoBlob());
           ps2.executeUpdate();
+
+          if (charity.getCategory() != null) {
+            for (String categoryRaw : charity.getCategory()) {
+              if (categoryRaw == null) continue;
+
+              String category = categoryRaw.toLowerCase().trim();
+
+              if (category.isEmpty()) continue;
+
+              ps3.setString(1, category);
+              ps3.executeUpdate();
+
+              ps4.setString(1, category);
+
+              try (ResultSet rs = ps4.executeQuery()) {
+                if (rs.next()) {
+                  int categoryId = rs.getInt("category_id");
+
+                  ps5.setInt(1, categoryId);
+                  ps5.setString(2, uuid);
+                  ps5.executeUpdate();
+                }
+              }
+            }
+          }
         }
+
       } catch (Exception e) {
         e.printStackTrace();
         throw new RuntimeException(e);
       }
 
-        // Integrity Check
+      // Integrity Check
       String createTemp =
           """
             CREATE TEMPORARY TABLE temp_api_charities (
@@ -141,8 +180,22 @@ AND NOT EXISTS (
             );
         """;
 
-      try (PreparedStatement ps = conn.prepareStatement(deleteSql)) {
-        ps.executeUpdate();
+      String deleteUnusedCategoriesSql =
+          """
+
+        DELETE FROM Categories c
+        WHERE NOT EXISTS (
+           SELECT 1
+           FROM Charity_Categories cc
+           WHERE cc.Categories_category_id = c.category_id
+       );
+        """;
+
+      try (PreparedStatement ps1 = conn.prepareStatement(deleteSql);
+          PreparedStatement ps2 = conn.prepareStatement(deleteUnusedCategoriesSql)) {
+
+        ps1.executeUpdate();
+        ps2.executeUpdate();
       }
 
       conn.commit();