Glock 21 vs 30 Size Comparison
The Glock 30 is 1.1 in (28 mm) shorter, 0.71 in (18 mm) lower and the same width than the Glock 21. With an empty magazine it weighs 2.82 oz (80 g) less. It holds 10 rounds in a standard magazine to the 21's 13. Both drawn to scale from Glock's published dimensions.
Glock 21 vs 30 side by side
Glock A
Glock B
Side profile
From behind
- Slide width
- 1.12 in1.12 in
- Same
- Overall width, with controls
- 1.38 in1.38 in
- Same
Tap the drawing to flip between the Glock 21, the Glock 30 and both.
Photos: Glock 17 Gen5 photo by Tony Webster, cut out by LeoPavouk (CC BY 2.0); Glock 43X photo by Kolomaznik (CC BY 4.0); Glock 17 Gen4 photo by Steve Dock, UK Ministry of Defence (OGL v1.0) Contains public sector information licensed under the Open Government Licence v1.0. Cut out and reshaped to each model's published size by GunPartPicker.
Quick answer
The Glock 30 is 1.1 in (28 mm) shorter, 0.71 in (18 mm) lower and the same width than the Glock 21. With an empty magazine it weighs 2.82 oz (80 g) less. It holds 10 rounds in a standard magazine to the 21's 13.
- Glock 21: 8.07 in long, 5.51 in tall, 1.38 in wide, 4.61 in barrel. Glock 30: 6.97 in long, 4.8 in tall, 1.38 in wide, 3.78 in barrel.
One square is one inch. Real Glock photos sized to Glock's published dimensions, checked September 27, 2026.
Is the Glock 21 or 30 bigger?
The Glock 21 is the bigger pistol. Against the Glock 30 it is 1.1 in (28 mm) longer and 0.71 in (18 mm) taller.
Glock 21 vs 30 dimensions
| Dimension | Glock 21 | Glock 30 | B vs A |
|---|---|---|---|
| Overall length | 8.07 in205 mm | 6.97 in177 mm | −1.1 in28 mm |
| Slide length | 7.52 in191 mm | 6.69 in170 mm | −0.83 in21 mm |
| Barrel length | 4.61 in117 mm | 3.78 in96 mm | −0.83 in21 mm |
| Height with magazine | 5.51 in140 mm | 4.8 in122 mm | −0.71 in18 mm |
| Overall width, with controls | 1.38 in35 mm | 1.38 in35 mm | Same |
| Slide width | 1.12 in28 mm | 1.12 in28 mm | Same |
| Trigger reach | 2.85 in72 mm | 2.85 in72 mm | Same |
| Weight, empty magazine | 29.1 oz825 g | 26.28 oz745 g | −2.82 oz80 g |
| Capacity, standard magazine | 13 rounds | 10 rounds | −3 |
| Caliber | .45 ACP | .45 ACP | Same |
| Glock catalog | Current model | Law enforcement catalog; retail stock still sells |
Glock 21 vs 30 grip length
The Glock 30 stands 0.71 in (18 mm) lower than the Glock 21 with a magazine in (4.8 in against 5.51 in), and the trigger reach is the same, 2.85 in (72 mm).
Glock 21 vs 30 barrel and slide length
The Glock 30 barrel is 0.83 in (21 mm) shorter: 3.78 in against 4.61 in. Its slide is 0.83 in (21 mm) shorter (6.69 in against 7.52 in).
Will a Glock 30 fit a Glock 21 holster?
It will go in, but loose. The Glock 30 slide is 0.83 in (21 mm) shorter than the Glock 21, so a molded Glock 21 holster may not retain it. Holster makers mold for exact models, so check the maker's fit list before you buy.
Is the Glock 30 compact or subcompact?
Glock puts the Glock 30 in its subcompact large frame class and the Glock 21 in its full size large frame class. Here is every current Glock at the same scale.
Subcompact slimline
Subcompact
Compact
Full size
Every card is to the same scale, lined up at the slide rear. Tap one to compare it or look at it alone.
Where can I buy a Glock 21 or 30 today?
Glock 21 in stock
In stock now. One listing per model family.
Glock 30 in stock
In stock now. One listing per model family.
More Glock 21 and 30 comparisons
Frequently Asked Questions
How much smaller is the Glock 30 than the Glock 21?
1.1 in (28 mm) shorter, 0.71 in (18 mm) lower and 0 in (0 mm) narrower, by Glock's published dimensions.
Which is lighter, the Glock 21 or the Glock 30?
The Glock 30, by 2.82 oz (80 g) with an empty magazine: 26.28 oz (745 g) against 29.1 oz (825 g) for the Glock 21.
Which holds more rounds, the Glock 21 or the Glock 30?
The Glock 21: 13 rounds in a standard magazine against 10 for the Glock 30, as Glock's spec pages list them.
Where do these Glock 21 and Glock 30 numbers come from?
From Glock's own US spec pages, checked September 27, 2026. Both guns are shown at one scale, as real Glock photos reshaped to those numbers.
Cite this tool: GunPartPicker, “Glock 21 vs 30 Size Comparison”, https://gunpartpicker.net/tools/glock-size-comparison/glock-21-vs-30. Data from the GunPartPicker catalog and real community builds, prices checked October 12, 2026. Free to cite with attribution.
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