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+<!DOCTYPE html>
+<html lang="de">
+<head>
+<meta charset="UTF-8">
+<title>1 TB verkauft, 931 GB angezeigt — wo gehen die 69 GB hin?</title>
+<style>
+  :root {
+    --dark: #1a1a2e;
+    --muted: #6b7280;
+    --soft: #f8fafc;
+    --border: #cbd5e1;
+    --hl: #d63384;
+    --marketing: #2563eb;
+    --os: #ea580c;
+  }
+  html, body { margin: 0; padding: 0; background: #fff; font-family: system-ui, -apple-system, sans-serif; color: var(--dark); }
+  body { padding: 32px 40px; }
+  h1 { text-align: center; margin: 0 0 6px; font-size: 1.75rem; }
+  .sub { text-align: center; color: var(--muted); margin-bottom: 24px; font-size: 1.05rem; }
+  .sub strong { color: var(--dark); }
+
+  .compare {
+    display: grid;
+    grid-template-columns: 1fr 80px 1fr;
+    gap: 18px;
+    max-width: 1100px;
+    margin: 0 auto;
+    align-items: stretch;
+  }
+
+  .side {
+    border: 2px solid;
+    border-radius: 12px;
+    padding: 18px 22px;
+    background: #fff;
+    display: flex;
+    flex-direction: column;
+    align-items: center;
+    gap: 10px;
+  }
+  .side.marketing { border-color: var(--marketing); }
+  .side.os        { border-color: var(--os); }
+
+  .side-tag {
+    font-size: 0.72rem;
+    font-weight: 700;
+    text-transform: uppercase;
+    letter-spacing: 0.12em;
+    color: var(--muted);
+  }
+  .side.marketing .side-name { color: var(--marketing); }
+  .side.os .side-name { color: var(--os); }
+  .side-name { font-size: 1.15rem; font-weight: 700; }
+
+  .label-mock {
+    background: var(--soft);
+    border: 1.5px solid var(--border);
+    border-radius: 8px;
+    padding: 14px 22px;
+    min-width: 240px;
+    text-align: center;
+    font-family: ui-monospace, monospace;
+    font-size: 0.85rem;
+    color: var(--muted);
+    line-height: 1.5;
+  }
+  .label-mock .big {
+    font-family: system-ui, sans-serif;
+    font-size: 2.2rem;
+    font-weight: 900;
+    display: block;
+    color: var(--dark);
+    line-height: 1.05;
+  }
+  .side.marketing .label-mock .big { color: var(--marketing); }
+  .side.os        .label-mock .big { color: var(--os); }
+  .label-mock .small-line { font-size: 0.78rem; }
+
+  .formel {
+    font-family: ui-monospace, monospace;
+    font-size: 0.85rem;
+    color: var(--muted);
+    text-align: center;
+    line-height: 1.6;
+  }
+  .formel strong { color: var(--dark); }
+
+  .arrow-col {
+    display: flex;
+    flex-direction: column;
+    align-items: center;
+    justify-content: center;
+    gap: 4px;
+    color: var(--muted);
+  }
+  .arrow-col svg { display: block; }
+  .arrow-col .why {
+    font-size: 0.78rem;
+    font-weight: 700;
+    color: var(--hl);
+    text-align: center;
+    line-height: 1.25;
+  }
+
+  .math-box {
+    margin-top: 22px;
+    max-width: 1100px;
+    margin-left: auto;
+    margin-right: auto;
+    background: var(--soft);
+    border: 1.5px solid var(--border);
+    border-radius: 10px;
+    padding: 16px 22px;
+  }
+  .math-box-head { font-size: 0.78rem; font-weight: 700; text-transform: uppercase; letter-spacing: 0.1em; color: var(--muted); margin-bottom: 8px; }
+  .math-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 10px 22px; font-family: ui-monospace, monospace; font-size: 0.9rem; line-height: 1.6; }
+  .math-grid .key { color: var(--muted); }
+  .math-grid .val { color: var(--dark); font-weight: 700; }
+  .math-grid .val.hl { color: var(--hl); }
+
+  .verdict {
+    margin-top: 18px;
+    max-width: 1100px;
+    margin-left: auto;
+    margin-right: auto;
+    text-align: center;
+    border: 2px solid var(--hl);
+    border-radius: 12px;
+    padding: 14px 22px;
+  }
+  .verdict-q { font-size: 1.05rem; font-weight: 700; color: var(--hl); }
+  .verdict-a { font-size: 0.93rem; color: var(--dark); margin-top: 4px; }
+  .verdict-a code { font-family: ui-monospace, monospace; background: #fff; padding: 1px 5px; border-radius: 4px; border: 1px solid var(--border); }
+</style>
+</head>
+<body>
+  <h1>„1 TB" gekauft — 931 GB im Finder. Wo sind die 69 GB hin?</h1>
+  <div class="sub">Nirgendwo. Es sind <strong>dieselben Byte</strong>. Nur zwei Welten zählen anders.</div>
+
+  <div class="compare">
+
+    <div class="side marketing">
+      <div class="side-tag">Auf der Verpackung</div>
+      <div class="side-name">Marketing</div>
+      <div class="label-mock">
+        <span class="big">1 TB</span>
+        <span class="small-line">externe SSD</span>
+      </div>
+      <div class="formel">
+        1 TB = <strong>10<sup>12</sup></strong> Byte<br>
+        = 1 000 000 000 000
+      </div>
+    </div>
+
+    <div class="arrow-col">
+      <svg viewBox="0 0 60 30" width="56" height="30"><path d="M5,15 L48,15 M42,7 L52,15 L42,23" stroke="#d63384" stroke-width="2.5" fill="none"/></svg>
+      <div class="why">geteilt durch<br>2<sup>30</sup></div>
+    </div>
+
+    <div class="side os">
+      <div class="side-tag">Im Finder · Explorer</div>
+      <div class="side-name">Betriebssystem</div>
+      <div class="label-mock">
+        <span class="big">931 GB</span>
+        <span class="small-line">eigentlich: 931 GiB</span>
+      </div>
+      <div class="formel">
+        1 GiB = <strong>2<sup>30</sup></strong> Byte<br>
+        = 1 073 741 824
+      </div>
+    </div>
+
+  </div>
+
+  <div class="math-box">
+    <div class="math-box-head">Die Rechnung</div>
+    <div class="math-grid">
+      <span class="key">Marketing schreibt</span>
+      <span class="val">1 TB = 1 000 000 000 000 Byte (Basis 10)</span>
+      <span class="key">Betriebssystem rechnet</span>
+      <span class="val">1 TiB = 1 099 511 627 776 Byte (Basis 2)</span>
+      <span class="key">1 TB in GiB umrechnen</span>
+      <span class="val hl">10<sup>12</sup> ÷ 2<sup>30</sup> ≈ 931,3 GiB — der Finder zeigt also „931 GB"</span>
+      <span class="key">Was die Studis sehen</span>
+      <span class="val">Etikett: GB · Anzeige: GB · Bedeutung: zwei verschiedene Dinge</span>
+    </div>
+  </div>
+
+  <div class="verdict">
+    <div class="verdict-q">Es fehlt nichts. Es wird nur in zwei Sprachen gezählt.</div>
+    <div class="verdict-a">Korrekt wären <code>GiB</code> (binär, 1024) und <code>GB</code> (dezimal, 1000). In der Realität verwenden beide Welten <code>GB</code> und meinen verschiedene Zahlen.</div>
+  </div>
+</body>
+</html>
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