diff --git a/app/app.py b/app/app.py
index 3c24a6c..bcf98f6 100644
--- a/app/app.py
+++ b/app/app.py
@@ -554,11 +554,26 @@ def upload_file():
     if not dest.is_dir():
         abort(400)
 
+    conflict = request.form.get("conflict", "overwrite")
+    if conflict not in ("backup", "overwrite", "rename", "skip"):
+        conflict = "overwrite"
+
     for f in files:
         name = secure_filename(f.filename or "")
         if not name:
             continue
-        f.save(dest / name)
+        out_path = dest / name
+        if out_path.exists():
+            if conflict == "skip":
+                continue
+            elif conflict == "backup":
+                try:
+                    out_path.rename(_backup_path(out_path))
+                except Exception:
+                    continue
+            elif conflict == "rename":
+                out_path = _auto_rename(out_path)
+        f.save(out_path)
 
     return redirect(url_for("browse", subpath=subpath) if subpath else url_for("browse"))
 
diff --git a/app/static/app.css b/app/static/app.css
index db1531c..d888214 100644
--- a/app/static/app.css
+++ b/app/static/app.css
@@ -165,6 +165,7 @@ main { max-width: 1100px; margin: 2rem auto; padding: 0 1.5rem 3rem; display: fl
 
 /* ── Upload ───────────────────────────────────────────────────────── */
 .upload-card h2 { margin-bottom: .8rem; }
+.upload-conflict { display: flex; align-items: center; gap: .8rem; flex-wrap: wrap; margin-bottom: .8rem; }
 .drop-zone { display: flex; flex-direction: column; align-items: center; justify-content: center; gap: .5rem; border: 2px dashed var(--border); border-radius: var(--radius); padding: 2rem 1.5rem; cursor: pointer; background: var(--bg); transition: border-color .15s, background .15s; text-align: center; position: relative; margin-bottom: 1rem; }
 .drop-zone:hover, .drop-zone:focus-within { border-color: var(--blue); background: var(--blue-light); }
 .drop-zone input[type=file] { position: absolute; inset: 0; opacity: 0; cursor: pointer; width: 100%; height: 100%; }
diff --git a/app/templates/browse.html b/app/templates/browse.html
index f30888f..71210ef 100644
--- a/app/templates/browse.html
+++ b/app/templates/browse.html
@@ -120,6 +120,15 @@
       <span class="drop-names" id="drop-names"></span>
       <input type="file" name="files" id="upload-input" multiple>
     </label>
+    <div class="upload-conflict">
+      <span class="resize-group-label">Si le fichier existe déjà</span>
+      <div class="resize-chips resize-chips--radio">
+        <label class="chip"><input type="radio" name="conflict" value="overwrite" checked><span>Écraser</span></label>
+        <label class="chip"><input type="radio" name="conflict" value="backup"><span>Backup</span></label>
+        <label class="chip"><input type="radio" name="conflict" value="rename"><span>Renommer</span></label>
+        <label class="chip"><input type="radio" name="conflict" value="skip"><span>Ignorer</span></label>
+      </div>
+    </div>
     <button type="submit" class="btn btn-primary" id="upload-btn" disabled>Envoyer</button>
   </form>
   <script>