Glock 17 vs 19 vs 45: which full-size 9mm to buy

Three 9mm Glocks account for most of what we sell: the full-size 17, the compact 19, and the 45, which puts the 19's slide on the 17's frame. They share a trigger, a magazine family and a manual of arms, and they differ by half an inch here and two rounds there. Those small differences decide which one you should own. This guide lays out the numbers, then the jobs, then a recommendation for each kind of buyer.

The numbers

• Glock 17 Gen 5: 4.49 inch barrel, about 8.03 inches long, 5.47 inches tall, 17-round magazine, roughly 22 ounces without a magazine.
• Glock 19 Gen 5: 4.02 inch barrel, about 7.36 inches long, 5.04 inches tall, 15-round magazine, roughly 21.5 ounces.
• Glock 45: 4.02 inch barrel, about 7.44 inches long, 5.47 inches tall, 17-round magazine, roughly 24 ounces, with front serrations and a flared magwell.

All three are 1.34 inches wide across the Gen 5 slide stop levers. Figures are Glock's published specifications and vary slightly by generation; check the product page for the exact pistol.

What half an inch of grip buys

The 17 and 45 share the full-size frame, which gives every finger a place and adds two rounds. That grip is the reason both shoot flatter and faster for most hands than the 19, and it is also the part of a pistol that prints under a shirt. The 19's shorter grip is the compromise that made it the most carried pistol in America: enough to hold, small enough to hide.

What half an inch of slide buys

The 17's longer slide gives a longer sight radius, roughly 6.5 inches against 6.0 on the 19 and 45, and a little more velocity. That helps iron-sight shooting at distance. With a red dot the sight radius stops mattering, which is why the 45 exists: full grip, short slide, dot on top, and a pistol that clears a holster a fraction faster than a 17.

Home defense

Buy the 17 or the 45. Concealment is irrelevant in a nightstand safe, capacity and grip matter, and both take a full-size rail light. Between them, the 17 for iron sights and the longest sight radius, the 45 for a dot and the flared magwell. The 19 is not wrong, only smaller.

Concealed carry

Buy the 19. It hides under a t-shirt in an appendix holster, it shoots like a full-size gun, and it has more holsters made for it than any pistol in history. Carry a 17-round magazine as the spare. The 45 carries like a 17, which is to say it needs a cover garment; some people do it and most of them own a 19 too.

Duty and open carry

Buy the 17 or the 45; agencies split between them. The 17 has thirty years of duty holsters and the sight radius; the 45 has the dot-ready MOS version, front serrations and the magwell. If the pistol rides in a retention holster on a belt, the 45's shorter slide is a small advantage on the draw and no disadvantage anywhere else.

Matches

Buy the 17 for iron-sight divisions, or the 34 which is a 17 with a longer slide; buy the 45 MOS or 17 MOS for carry optics. The 19 competes and does fine, but the shorter grip costs a little on reloads and the shorter slide costs a little at distance.

One pistol for everything

The 19. It is the only one of the three that carries well, and it does the other jobs at ninety percent of the others' ability. Add a 17-round spare magazine for the nightstand and a rail light that fits the 19's rail, and one pistol covers the house, the belt and the range. If concealment is never on the list, the 45 is the better single pistol.

Recoil and ammunition

All three fire the same 9mm and the differences in felt recoil are small: the 17 and 45 are steadier because of the full grip and the extra ounce or two, the 19 a touch snappier. Every one is rated for +P ammunition and runs the common 115, 124 and 147 grain loads. Practice with full metal jacket and load a proven hollow point for defense; shoot a box of the defensive load through the pistol you buy before you rely on it, whichever of the three it is.

Holsters, magazines and parts

The 19 and 45 share a slide length and often a holster if the holster is open at the top of the grip; the 17 needs its own. The 17 and 45 share magazines; the 19 takes its own 15-round magazine and every longer 9mm Glock magazine. All three Gen 5 pistols share trigger parts, sights, strikers, extractors and the connector; the 19 and 45 share barrels and recoil assemblies. Whichever you buy, the parts world is the same.

Generation and MOS

All three come as Gen 5, the 17 and 19 also as Gen 3 and Gen 4, and all three as MOS. Buy Gen 5 unless you are in a roster state; buy MOS if a dot is in the plan within a year. The Gen 5 vs Gen 4 guide and the MOS guide cover those choices, and buying a Glock online explains the transfer. Browse the Glock 17, Glock 19 and Glock 45; every pistol ships to a licensed dealer near you.

General information, not legal advice. Current as of September 2026. Laws change; check the official source before you act.