Weight limits vary by type: small soft carriers are often rated around 12 lb, midrange carriers commonly list limits of about 18–24 lb, and large collapsible crates can be listed up to 70 lb (some specify an ideal pet weight range of 50–70 lb).

Dimensions vary widely by style. Many soft carriers list lengths of about 12.5–17 in, heights near 10–16 in, and widths around 8–11 in. Larger collapsible crates appear at sizes such as 36 x 25 x 25 in.

Carriers typically use mesh panels, zip-up mesh windows, and three-sided breathable mesh to promote airflow and give pets visibility while traveling.

Common access options include two-sided or two-way entry, full top openings or zippered top flaps, and zippered side openings or doors for easy pet entry and quick checks.

Many carriers include padded shoulder straps (and some padded back straps), waist and chest buckles for added support, resilient shoulder padding, and sturdy handles to make carrying easier on walks or longer trips.

Many soft-sided carriers require no assembly. Larger metal-frame or collapsible crates may require adult assembly, and some models include basic tools or hardware to complete setup.