diff --git a/web/src/components/DataTable.jsx b/web/src/components/DataTable.jsx
index cb61d9e..298e492 100644
--- a/web/src/components/DataTable.jsx
+++ b/web/src/components/DataTable.jsx
@@ -44,8 +44,14 @@ export default function DataTable({
   const [filterShown, setFilterShown] = useState(true);
   const [openFilter, setOpenFilter] = useState(null);
   const [collapsed, setCollapsed] = useState(() => new Set());
+  const [hidden, setHidden] = useState(
+    () => new Set((loadPersisted(id).hidden || []).filter((k) => colByKey[k])),
+  );
+  const [chooserOpen, setChooserOpen] = useState(false);
 
-  useEffect(() => { savePersisted(id, { order, widths }); }, [id, order, widths]);
+  useEffect(() => {
+    savePersisted(id, { order, widths, hidden: [...hidden] });
+  }, [id, order, widths, hidden]);
 
   // Containerbreite messen, damit die grow-Spalte den Rest füllt.
   const wrapRef = useRef(null);
@@ -59,7 +65,39 @@ export default function DataTable({
     return () => ro.disconnect();
   }, []);
 
-  const orderedCols = order.map((k) => colByKey[k]).filter(Boolean);
+  const allOrdered = order.map((k) => colByKey[k]).filter(Boolean);
+  const orderedCols = allOrdered.filter((c) => !hidden.has(c.key));
+
+  // Spalten-Wähler-Popover.
+  const chooserBtn = useRef(null);
+  const chooserPop = useRef(null);
+  const [chooserPos, setChooserPos] = useState(null);
+  useLayoutEffect(() => {
+    if (chooserOpen && chooserBtn.current) {
+      const r = chooserBtn.current.getBoundingClientRect();
+      setChooserPos({ left: Math.min(r.left, window.innerWidth - 240), top: r.bottom + 4 });
+    }
+  }, [chooserOpen]);
+  useEffect(() => {
+    if (!chooserOpen) return undefined;
+    function onDoc(e) {
+      if (chooserBtn.current?.contains(e.target) || chooserPop.current?.contains(e.target)) return;
+      setChooserOpen(false);
+    }
+    document.addEventListener("mousedown", onDoc);
+    return () => document.removeEventListener("mousedown", onDoc);
+  }, [chooserOpen]);
+
+  function toggleHidden(key) {
+    setHidden((s) => {
+      const n = new Set(s);
+      if (n.has(key)) { n.delete(key); return n; }
+      // Mindestens eine Spalte sichtbar lassen.
+      if (allOrdered.filter((c) => !n.has(c.key) && c.key !== key).length === 0) return s;
+      n.add(key);
+      return n;
+    });
+  }
 
   const isGrow = (c) => c.grow && widths[c.key] == null;
   const fixedWidth = (c) => widths[c.key] ?? c.width ?? DEFAULT_WIDTH;
@@ -224,6 +262,7 @@ export default function DataTable({
   function resetColumns() {
     setOrder(columns.map((c) => c.key));
     setWidths({});
+    setHidden(new Set());
     savePersisted(id, {});
   }
 
@@ -235,9 +274,26 @@ export default function DataTable({
           <Icon name="search" size={14} />Filter
         </button>
         <button type="button" className="btn sm ghost" onClick={() => setFilters({})}>Filter löschen</button>
+        <button type="button" ref={chooserBtn} className={`btn sm ${chooserOpen ? "" : "ghost"}`}
+          onClick={() => setChooserOpen((o) => !o)}>
+          <Icon name="settings" size={14} />Spalten
+        </button>
         <button type="button" className="btn sm ghost" onClick={resetColumns}>Spalten zurücksetzen</button>
         {toolbarExtra}
       </div>
+      {chooserOpen && chooserPos && createPortal(
+        <div ref={chooserPop} className="dt-pop" style={{ left: chooserPos.left, top: chooserPos.top }}>
+          <div className="dt-pop-list">
+            {allOrdered.map((c) => (
+              <label key={c.key} className="dt-pop-opt">
+                <input type="checkbox" checked={!hidden.has(c.key)} onChange={() => toggleHidden(c.key)} />
+                <span>{c.header || c.key}</span>
+              </label>
+            ))}
+          </div>
+        </div>,
+        document.body,
+      )}
       <div className="table-wrap" ref={wrapRef}>
         <table className="table datatable" style={{ width: totalWidth ? `${totalWidth}px` : "100%" }}>
           <colgroup>