diff --git a/scripts/gen_rack.py b/scripts/gen_rack.py
index 1b01fc7..a9d592a 100644
--- a/scripts/gen_rack.py
+++ b/scripts/gen_rack.py
@@ -115,3 +115,123 @@ def check_overlaps(items: list[dict]) -> None:
                         f"U{uu} {f}: {name} overlaps {occupied[key]}"
                     )
                 occupied[key] = name
+
+
+def _esc(s: object) -> str:
+    return str(s).replace("&", "&amp;").replace("<", "&lt;").replace(">", "&gt;")
+
+
+def _sorted_items(items: list[dict]) -> list[dict]:
+    """Deterministic order: faced items by U then hostname, 0U items last."""
+    return sorted(
+        items,
+        key=lambda i: (
+            0 if i.get("rack_face") not in ZERO_U_FACES else 1,
+            i.get("rack_u", 0) if isinstance(i.get("rack_u"), int) else 0,
+            i.get("hostname", ""),
+        ),
+    )
+
+
+def render_svg(rack: str, items: list[dict]) -> str:
+    U_H = 20
+    COL_W = 240
+    LABEL_W = 30
+    RAIL_W = 16
+    PAD = 12
+    GAP = 50
+    TITLE_H = 28
+
+    items = _sorted_items(items)
+    left_items = [i for i in items if i.get("rack_face") == "left"]
+    right_items = [i for i in items if i.get("rack_face") == "right"]
+
+    body_h = RACK_UNITS * U_H
+    height = PAD + TITLE_H + body_h + PAD
+    front_x = PAD + len(left_items) * RAIL_W + LABEL_W
+    rear_x = front_x + COL_W + GAP
+    width = rear_x + COL_W + len(right_items) * RAIL_W + PAD
+    top = PAD + TITLE_H
+
+    def u_y(u: int) -> int:
+        # U1 at the top; U numbers increase downward.
+        return top + (u - 1) * U_H
+
+    p: list[str] = []
+    p.append(
+        f'<svg xmlns="http://www.w3.org/2000/svg" width="{width}" '
+        f'height="{height}" viewBox="0 0 {width} {height}" '
+        f'font-family="sans-serif" font-size="11">'
+    )
+    p.append(f'<rect width="{width}" height="{height}" fill="#ffffff"/>')
+    p.append(
+        f'<text x="{PAD}" y="{PAD + 16}" font-size="16" '
+        f'font-weight="bold">Rack {_esc(rack)}</text>'
+    )
+
+    for col_x, col_label in ((front_x, "front"), (rear_x, "rear")):
+        p.append(
+            f'<text x="{col_x + COL_W // 2}" y="{top - 6}" '
+            f'text-anchor="middle" font-weight="bold">{col_label}</text>'
+        )
+        for u in range(1, RACK_UNITS + 1):
+            y = u_y(u)
+            p.append(
+                f'<rect x="{col_x}" y="{y}" width="{COL_W}" height="{U_H}" '
+                f'fill="#f5f5f5" stroke="#e0e0e0"/>'
+            )
+
+    # U numbers in the gutter left of the front column.
+    for u in range(1, RACK_UNITS + 1):
+        y = u_y(u)
+        p.append(
+            f'<text x="{front_x - 4}" y="{y + 14}" text-anchor="end" '
+            f'fill="#999">{u}</text>'
+        )
+
+    def draw_device(fm: dict, col_x: int) -> None:
+        u = fm["rack_u"]
+        h = fm["u_height"]
+        y = u_y(u)
+        box_h = h * U_H
+        color = KIND_COLORS.get(fm.get("kind", ""), DEFAULT_COLOR)
+        name = fm.get("hostname", "?")
+        urange = f"U{u}" if h == 1 else f"U{u}–U{u + h - 1}"
+        p.append(
+            f'<rect x="{col_x + 1}" y="{y + 1}" width="{COL_W - 2}" '
+            f'height="{box_h - 2}" rx="3" fill="{color}" stroke="#333"/>'
+        )
+        p.append(
+            f'<text x="{col_x + COL_W // 2}" y="{y + box_h // 2 + 4}" '
+            f'text-anchor="middle" fill="#ffffff">'
+            f'{_esc(name)} ({urange})</text>'
+        )
+
+    for fm in items:
+        face = fm.get("rack_face")
+        if face in ("front", "both"):
+            draw_device(fm, front_x)
+        if face in ("rear", "both"):
+            draw_device(fm, rear_x)
+
+    def draw_rail(fm: dict, x: int) -> None:
+        color = KIND_COLORS.get(fm.get("kind", ""), DEFAULT_COLOR)
+        name = fm.get("hostname", "?")
+        cx = x + RAIL_W // 2
+        cy = top + body_h // 2
+        p.append(
+            f'<rect x="{x}" y="{top}" width="{RAIL_W}" height="{body_h}" '
+            f'fill="{color}" stroke="#333"/>'
+        )
+        p.append(
+            f'<text x="{cx}" y="{cy}" text-anchor="middle" fill="#ffffff" '
+            f'transform="rotate(-90 {cx} {cy})">{_esc(name)}</text>'
+        )
+
+    for idx, fm in enumerate(left_items):
+        draw_rail(fm, PAD + idx * RAIL_W)
+    for idx, fm in enumerate(right_items):
+        draw_rail(fm, rear_x + COL_W + idx * RAIL_W)
+
+    p.append("</svg>")
+    return "\n".join(p) + "\n"
diff --git a/tests/test_gen_rack.py b/tests/test_gen_rack.py
index 3829512..4c073f1 100644
--- a/tests/test_gen_rack.py
+++ b/tests/test_gen_rack.py
@@ -74,3 +74,28 @@ def test_overlaps_ignores_zero_u_rails():
         item(hostname="p2", rack_face="left"),
     ]
     gen_rack.check_overlaps(items)  # no raise
+
+
+def test_render_svg_has_two_columns_of_48_slots():
+    svg = gen_rack.render_svg("rack01", [])
+    # one faint slot rect per U per column (front + rear)
+    assert svg.count('fill="#f5f5f5"') == 2 * gen_rack.RACK_UNITS
+    assert svg.startswith("<svg")
+    assert svg.rstrip().endswith("</svg>")
+
+
+def test_render_svg_includes_device_label():
+    items = [item(hostname="mf00", rack_u=1, u_height=2, rack_face="front")]
+    svg = gen_rack.render_svg("rack01", items)
+    assert "mf00" in svg
+    assert "U1" in svg
+
+
+def test_render_svg_is_deterministic():
+    items = [
+        item(hostname="b", rack_u=3, u_height=1, rack_face="front"),
+        item(hostname="a", rack_u=1, u_height=1, rack_face="rear"),
+    ]
+    assert gen_rack.render_svg("rack01", items) == gen_rack.render_svg(
+        "rack01", list(reversed(items))
+    )