Most half sheet pans measure about 18 inches long by 13 inches wide with a rim around 1 inch high. Some home-kitchen versions run slightly smaller (for example, ~17.5 x 12 inches) to slide into tighter ovens. Exact outer dimensions can vary by item, so it’s helpful to check the product specs.

• Typical outer size: ~18" x 13" x 1"
• Common variations: ~17.6" x 12" to 18" x 13"
• Uses: cookies, sheet-pan dinners, roasting vegetables

If you’re unsure about fit, compare the listed outer measurements to your oven’s interior space, leaving a little clearance for airflow.

A half sheet pan is larger than a 9x13. Here’s the quick comparison:

• Half sheet: about 18" x 13" with a ~1" rim. It offers roughly double the surface area of a 9x13.
• 9x13 pan: often called a quarter sheet (~9" x 13" x 1"), or it may be a 9x13 baking dish with taller sides.

Because the capacities differ, batter or food spread will change. If you’re swapping between them, consider scaling recipe quantities and keep an eye on bake times—thinner layers typically cook faster, while thicker layers may need extra time.

It mainly comes down to size and kitchen setup:

• Full sheet pan: about 26" x 18" with a ~1" rim. Common in commercial kitchens and often too large for standard home ovens.
• Half sheet pan: about 18" x 13" with a ~1" rim. Sized to fit most home ovens more comfortably.

Both styles are rimmed, flat metal trays used for baking and roasting. You’ll find options in aluminum, stainless or carbon steel, and nonstick. To choose, check the pan’s outer dimensions against your oven’s interior so you get an easy fit without crowding the sides.

It’s a rectangular, rimmed baking tray with low sides (around 1 inch). Typical traits include:

• Size: roughly 18" x 13" outer dimensions
• Rim: rolled or reinforced edge that can help reduce warping
• Materials: aluminum, stainless steel, or carbon steel; some have nonstick coatings
• Extras: some sets include fitted lids or cooling racks; certain pans feature textured surfaces for airflow

Finishes range from natural metal to colored nonstick. While details vary by item, the overall profile is flat and sturdy with ample surface area for cookies, sheet cakes, roasting, and general oven cooking.

A quick measuring check can help you decide:

1. Measure the interior oven width between the rack guides and the depth with the door closed.
2. Compare those numbers to the pan’s outer dimensions—a true half sheet is about 18" x 13" with a ~1" rim.
3. Leave a bit of clearance for airflow and easy in/out.

If space is tight, consider slightly smaller half sheets (around 17.5" x 12") or step down to a quarter sheet (~9" x 13"). Product pages list exact measurements, which can make it easier to match a pan to your oven.