Heckler & Koch USP45 (V1) vs Heckler & Koch USP9 Compact (V1)

Heckler & Koch publishes both as USP models. They are chambered differently — the USP45 (V1) in .45 ACP, the USP9 Compact (V1) in 9x19mm Parabellum — so nothing below compares their cartridges. The USP45 (V1) is 28 mm / 1.1 in longer overall; its barrel is 21 mm / 0.83 in longer; the USP9 Compact (V1) lists 1 round more of standard capacity. One field is not comparable — overall height — because the makers publish them on different measurement bases.

Computed differences06

Field	Difference
Overall length	28 mm / 1.1 in (USP45 (V1) is greater)
Overall width	3 mm / 0.12 in (USP9 Compact (V1) is greater)
Overall height	Not comparable — USP45 (V1): no basis stated; USP9 Compact (V1): HK's metric cell is blank in this caliber's row, so the millimetre figure is converted from its published 5.00 in
Barrel length	21 mm / 0.83 in (USP45 (V1) is greater)
Weight	Not published by both
Standard capacity	1 round (USP9 Compact (V1) is greater)

How these differences are computed: each is the arithmetic difference between the two published figures, and it is only shown where both sources measured the field the same way. Where a source states a measurement basis the other does not match, the row says so instead of subtracting — figures on different bases are not comparable even when the numbers sit side by side. Differences marked ≈ involve at least one figure this directory converted between unit systems, so the difference is no more precise than that conversion.

Size, to scale

Heckler & Koch USP45 (V1)Length 201 mm / 7.91 inWidth 32 mm / 1.26 in
Heckler & Koch USP9 Compact (V1)Length 173 mm / 6.81 inWidth 35 mm / 1.38 in

Boxes, not silhouettes: makers publish a pistol's overall envelope, not its shape, so that is all this draws. Every box is aligned at the rear and drawn at one fixed scale, the same on every page of this site, so drawings compare across pages. It is not life-size on your screen. Heights are not drawn because the heights are not published on one stated basis (USP45 (V1): no basis stated; USP9 Compact (V1): HK's metric cell is blank in this caliber's row, so the millimetre figure is converted from its published 5.00 in).

Published fields, side by side

Field	USP45 (V1)	USP9 Compact (V1)
Manufacturer	Heckler & Koch	Heckler & Koch
Chambering	.45 ACP	9x19mm Parabellum
Overall dimensions	201 × 32 × 142.5 mm / 7.91 × 1.26 × 5.61 in	173 × 35 × ≈127 mm / 6.81 × 1.38 × 5 in (height: HK's metric cell is blank in this caliber's row, so the millimetre figure is converted from its published 5.00 in)
Barrel length	112 mm / 4.41 in	91 mm / 3.58 in
Weight	887 g / 31.29 oz (HK's own column heading)	Not published
Standard capacity	12 rounds	13 rounds
Trigger pull	51 N / ≈11.47 lb (double-action); 20 N / ≈4.5 lb (single-action)	51 N / ≈11.47 lb (double-action); 20 N / ≈4.5 lb (single-action)
Verification	Source verified 2026-08-13	Source verified 2026-08-13

Reference information only. Not legal, purchasing, training, carry, storage, or assembly advice. Manufacturer technical data are rounded and may change without notice. Spotted an error? Submit a correction.