diff --git a/frontend/src/tools/devtools.jsx b/frontend/src/tools/devtools.jsx
index 0880653..5832534 100644
--- a/frontend/src/tools/devtools.jsx
+++ b/frontend/src/tools/devtools.jsx
@@ -585,30 +585,57 @@ function DatetimeRechner({ mobile }) {
 
   // ── Tab 2: Geburtstag ──
   const [bday, setBday] = useState('');
+  const [bdayTime, setBdayTime] = useState('');
   const [bdayResult, setBdayResult] = useState(null);
 
-  function calcBday(val) {
-    setBday(val);
-    if (!val) { setBdayResult(null); return; }
-    const birth = new Date(val);
+  function calcBday(date, time) {
+    const dateVal = date ?? bday;
+    const timeVal = time ?? bdayTime;
+    setBday(dateVal);
+    setBdayTime(timeVal);
+    if (!dateVal) { setBdayResult(null); return; }
+    // Build birth datetime: if time given use it, else midnight
+    const birthStr = timeVal ? `${dateVal}T${timeVal}:00` : `${dateVal}T00:00:00`;
+    const birth = new Date(birthStr);
     if (isNaN(birth)) { setBdayResult(null); return; }
+    const hasTime = !!timeVal;
     const today = new Date();
-    let age = today.getFullYear() - birth.getFullYear();
-    const hadBday = today.getMonth() > birth.getMonth() ||
-      (today.getMonth() === birth.getMonth() && today.getDate() >= birth.getDate());
-    if (!hadBday) age--;
 
-    const nextBday = new Date(today.getFullYear(), birth.getMonth(), birth.getDate());
+    // Age in years
+    let ageY = today.getFullYear() - birth.getFullYear();
+    let ageM = today.getMonth() - birth.getMonth();
+    let ageD = today.getDate() - birth.getDate();
+    if (ageD < 0) { ageM--; const prev = new Date(today.getFullYear(), today.getMonth(), 0); ageD += prev.getDate(); }
+    if (ageM < 0) { ageY--; ageM += 12; }
+
+    // Hours and minutes since last birthday (only if time entered)
+    let ageH = null, ageMi = null;
+    if (hasTime) {
+      ageH = today.getHours() - birth.getHours();
+      ageMi = today.getMinutes() - birth.getMinutes();
+      if (ageMi < 0) { ageH--; ageMi += 60; }
+      if (ageH < 0)  { ageD--;  ageH  += 24;
+        if (ageD < 0) { ageM--; const prev = new Date(today.getFullYear(), today.getMonth(), 0); ageD += prev.getDate();
+          if (ageM < 0) { ageY--; ageM += 12; } } }
+    }
+
+    // Next birthday
+    const nextBday = new Date(today.getFullYear(), birth.getMonth(), birth.getDate(),
+      hasTime ? birth.getHours() : 0, hasTime ? birth.getMinutes() : 0, 0);
     if (nextBday <= today) nextBday.setFullYear(today.getFullYear()+1);
-    const diffMs  = nextBday - today;
-    const diffD   = (diffMs / 86400000).toFixed(1);
-    const totalD  = Math.floor((today - birth) / 86400000);
-    const nextWday = WEEKDAYS[nextBday.getDay()];
+    const diffMs = nextBday - today;
+    const diffD  = (diffMs / 86400000).toFixed(1);
+    const totalMs = today - birth;
+    const totalD = (totalMs / 86400000).toFixed(1);
 
-    setBdayResult({ age, diffD, totalD,
+    // Age string
+    let ageStr = `${ageY} Jahre, ${ageM} Monate, ${ageD} Tage`;
+    if (hasTime && ageH !== null) ageStr += `, ${ageH} Std. ${pad2(ageMi)} Min.`;
+
+    setBdayResult({ ageStr, diffD, totalD,
       wday: WEEKDAYS[birth.getDay()],
-      geburtstag: `${pad2(birth.getDate())}.${pad2(birth.getMonth()+1)}.${birth.getFullYear()}`,
-      nextDate: `${pad2(nextBday.getDate())}.${pad2(nextBday.getMonth()+1)}.${nextBday.getFullYear()} (${nextWday})`,
+      geburtstag: `${pad2(birth.getDate())}.${pad2(birth.getMonth()+1)}.${birth.getFullYear()}${hasTime?' '+timeVal:''}`,
+      nextDate: `${pad2(nextBday.getDate())}.${pad2(nextBday.getMonth()+1)}.${nextBday.getFullYear()} (${WEEKDAYS[nextBday.getDay()]})`,
     });
   }
 
@@ -704,24 +731,29 @@ function DatetimeRechner({ mobile }) {
           <div style={{display:'flex',alignItems:'flex-end',gap:10,marginBottom:16,flexWrap:'wrap'}}>
             <div>
               <div style={lbl}>Geburtsdatum</div>
-              <input style={{...inp, maxWidth:220}} type="date" value={bday}
-                onChange={e=>calcBday(e.target.value)}/>
+              <input style={{...inp, maxWidth:180}} type="date" value={bday}
+                onChange={e=>calcBday(e.target.value, null)}/>
             </div>
-            {!!bday && <button style={{...S.btn('#ff6b9d',false), fontSize:11, padding:'6px 14px'}}
-              onClick={()=>{ setBday(''); setBdayResult(null); }}>✕ Leeren</button>}
+            <div>
+              <div style={lbl}>Uhrzeit (optional)</div>
+              <input style={{...inp, maxWidth:130}} type="time" value={bdayTime}
+                onChange={e=>calcBday(null, e.target.value)}/>
+            </div>
+            {!!(bday||bdayTime) && <button style={{...S.btn('#ff6b9d',false), fontSize:11, padding:'6px 14px'}}
+              onClick={()=>{ setBday(''); setBdayTime(''); setBdayResult(null); }}>✕ Leeren</button>}
           </div>
           {bdayResult && (
             <div>
               <DtRow label="Geburtsdatum" value={`${bdayResult.geburtstag} (${bdayResult.wday})`}/>
-              <DtRow label="Alter" value={`${bdayResult.age} Jahre`}/>
+              <DtRow label="Alter" value={bdayResult.ageStr}/>
               <DtRow label="Nächster Geburtstag" value={bdayResult.nextDate}/>
               <DtRow label="Tage bis Geburtstag" value={`${bdayResult.diffD} Tage`}/>
-              <DtRow label="Gelebte Tage" value={`${bdayResult.totalD.toLocaleString('de-DE')} Tage`} muted/>
+              <DtRow label="Gelebte Tage" value={`${Number(bdayResult.totalD).toLocaleString('de-DE')} Tage`} muted/>
             </div>
           )}
           {!bdayResult && (
             <div style={{color:'rgba(255,255,255,0.4)',fontFamily:'monospace',fontSize:11}}>
-              Geburtsdatum eingeben
+              Geburtsdatum eingeben · Uhrzeit ist optional
             </div>
           )}
         </div>