diff --git a/frontend/src/tools/devtools.jsx b/frontend/src/tools/devtools.jsx
index 626ac26..2a7b510 100644
--- a/frontend/src/tools/devtools.jsx
+++ b/frontend/src/tools/devtools.jsx
@@ -388,7 +388,7 @@ function ElektroRechner({ mobile }) {
           </ElektroSection>
 
           {/* Leistung */}
-          <ElektroSection title="🔋 Leistung  P = U · I">
+          <ElektroSection title="🔋 Leistung  P = U · I = U²/R = I²·R">
             <div style={{ display:'flex', gap:8, marginBottom:10, flexWrap:'wrap' }}>
               <ElektroInp vals={vals} setVals={setVals} k="u2" label="Spannung"   unit="V"/>
               <ElektroInp vals={vals} setVals={setVals} k="i2" label="Strom"      unit="A"/>