diff --git a/backend/src/app/rpc/commands/auth.clj b/backend/src/app/rpc/commands/auth.clj
index 5444273862..933411a489 100644
--- a/backend/src/app/rpc/commands/auth.clj
+++ b/backend/src/app/rpc/commands/auth.clj
@@ -258,7 +258,8 @@
   (validate-register-attempt! cfg params)
 
   (let [email   (profile/clean-email email)
-        profile (profile/get-profile-by-email pool email)]
+        profile (profile/get-profile-by-email pool email)
+        fullname (d/normalize-string fullname)]
 
     ;; SECURITY: refuse to issue a prepared-register token when an active
     ;; profile already exists for this email.
@@ -359,6 +360,9 @@
         is-active (:is-active params false)
         theme     (:theme params nil)
         email     (str/lower email)
+        fullname  (d/normalize-string (:fullname params))
+        locale    (d/normalize-string locale)
+        theme     (d/normalize-string theme)
 
         photo-id  (some->> (or (:oidc/picture props)
                                (:google/picture props)
@@ -367,7 +371,7 @@
                            (import-profile-picture cfg))
 
         params    {:id id
-                   :fullname (:fullname params)
+                   :fullname fullname
                    :email email
                    :auth-backend backend
                    :lang locale
diff --git a/backend/src/app/rpc/commands/profile.clj b/backend/src/app/rpc/commands/profile.clj
index a26fc9ea9e..5e5d08b6df 100644
--- a/backend/src/app/rpc/commands/profile.clj
+++ b/backend/src/app/rpc/commands/profile.clj
@@ -163,6 +163,9 @@
   ;; it or not for explicit locking and avoid concurrent updates of
   ;; the same row/object.
   (let [profile (get-profile conn profile-id ::db/for-update true)
+        fullname (d/normalize-string fullname)
+        lang     (d/normalize-string lang)
+        theme    (d/normalize-string theme)
         ;; Update the profile map with direct params
         profile (-> profile
                     (assoc :fullname fullname)
diff --git a/backend/src/app/rpc/commands/projects.clj b/backend/src/app/rpc/commands/projects.clj
index 12da9bb7c5..cfb03a2f0d 100644
--- a/backend/src/app/rpc/commands/projects.clj
+++ b/backend/src/app/rpc/commands/projects.clj
@@ -6,6 +6,7 @@
 
 (ns app.rpc.commands.projects
   (:require
+   [app.common.data :as d]
    [app.common.data.macros :as dm]
    [app.common.exceptions :as ex]
    [app.common.schema :as sm]
@@ -259,7 +260,8 @@
    ::db/transaction true}
   [{:keys [::db/conn]} {:keys [::rpc/profile-id id name] :as params}]
   (check-edition-permissions! conn profile-id id)
-  (let [project (db/get-by-id conn :project id ::sql/for-update true)]
+  (let [project (db/get-by-id conn :project id ::sql/for-update true)
+        name    (d/normalize-string name)]
     (db/update! conn :project
                 {:name name}
                 {:id id})
diff --git a/backend/src/app/rpc/commands/teams.clj b/backend/src/app/rpc/commands/teams.clj
index 76d9b162c5..3ecf6f121c 100644
--- a/backend/src/app/rpc/commands/teams.clj
+++ b/backend/src/app/rpc/commands/teams.clj
@@ -652,6 +652,7 @@
   (let [id         (or id (uuid/next))
         is-default (if (boolean? is-default) is-default false)
         features   (db/create-array conn "text" features)
+        name       (d/normalize-string name)
         team       (db/insert! conn :team
                                {:id id
                                 :name name
@@ -688,6 +689,7 @@
   [conn {:keys [id team-id name is-default created-at modified-at]}]
   (let [id         (or id (uuid/next))
         is-default (if (boolean? is-default) is-default false)
+        name       (d/normalize-string name)
         params     {:id id
                     :name name
                     :team-id team-id
@@ -718,9 +720,10 @@
    ::db/transaction true}
   [{:keys [::db/conn] :as cfg} {:keys [::rpc/profile-id id name]}]
   (check-edition-permissions! conn profile-id id)
-  (db/update! conn :team
-              {:name name}
-              {:id id})
+  (let [name (d/normalize-string name)]
+    (db/update! conn :team
+                {:name name}
+                {:id id}))
   nil)
 
 
diff --git a/common/src/app/common/data.cljc b/common/src/app/common/data.cljc
index 7cbfdcc4f5..418c6e5bd5 100644
--- a/common/src/app/common/data.cljc
+++ b/common/src/app/common/data.cljc
@@ -1173,6 +1173,15 @@
   [key coll]
   (sort-by key natural-compare coll))
 
+(defn normalize-string
+  "Normalizes a string by trimming leading/trailing whitespace.
+   Returns empty string for nil input. Non-string input is returned unchanged."
+  [s]
+  (cond
+    (nil? s) ""
+    (string? s) (str/trim s)
+    :else s))
+
 (defn sanitize-string [s]
   (if s
     (-> s
diff --git a/common/test/common_tests/data_test.cljc b/common/test/common_tests/data_test.cljc
index 39f3370de8..46f12fd8fb 100644
--- a/common/test/common_tests/data_test.cljc
+++ b/common/test/common_tests/data_test.cljc
@@ -36,6 +36,24 @@
   (t/is (= "" (d/get-initials nil)))
   (t/is (= "" (d/get-initials "!!! ???"))))
 
+(t/deftest normalize-string-test
+  ;; nil input returns empty string
+  (t/is (= "" (d/normalize-string nil)))
+  ;; empty string returns empty string
+  (t/is (= "" (d/normalize-string "")))
+  ;; leading whitespace is trimmed
+  (t/is (= "hello" (d/normalize-string "  hello")))
+  ;; trailing whitespace is trimmed
+  (t/is (= "hello" (d/normalize-string "hello  ")))
+  ;; both leading and trailing whitespace are trimmed
+  (t/is (= "hello" (d/normalize-string "  hello  ")))
+  ;; internal whitespace is preserved
+  (t/is (= "hello world" (d/normalize-string "  hello world  ")))
+  ;; non-string input is returned unchanged
+  (t/is (= 42 (d/normalize-string 42)))
+  (t/is (= :keyword (d/normalize-string :keyword)))
+  (t/is (= true (d/normalize-string true))))
+
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 ;; Ordered Data Structures
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;