Can I go straight from the Brooks Glycerin 21 to the Glycerin 23 and skip the Glycerin 22?

Yes, but going Glycerin 21 to Glycerin 23 means taking one change in a single step: the Glycerin 22 is where the ride moved. The drop also goes 10 mm to 8 mm across the jump, so give it a week of easy running.

How much did the weight change across these two updates?

0.8 oz on in total, 9.8 oz to 10.6 oz in a men's US 9. The Glycerin 22 took it to 10.2 oz first.

Is the Glycerin 22 the better buy than either of these?

On paper it splits them: 10.2 oz against 9.8 oz for the Glycerin 21 and 10.6 oz for the Glycerin 23, on a 38 mm heel and a $165 list price. Whether that is worth chasing depends on what the Glycerin 22 update actually did, which the section above works through.

Did the Glycerin get taller between the Glycerin 21 and the Glycerin 23?

Heel stack went 38 mm to 38 mm, by way of 38 mm on the Glycerin 22. Drop moved 10 mm to 8 mm, which is the change your calves and Achilles notice.

Where does the Glycerin 23 sit in the Glycerin lineup now?

It is the current model, two versions on from the Glycerin 21 and the newest one you can buy at full retail.

Brooks Glycerin 21 vs Glycerin 23

Two versions apart. Updated September 10, 2026. Specs are men's US 9.

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THE SHORT ANSWER

Two updates and 3 years separate the Brooks Glycerin 21 from the Glycerin 23. Net change: 0.8 oz heavier, a drop change from 10 mm to 8 mm, a new midsole, $15 more at list. The Glycerin 22 is where the character changed, and that is the update Glycerin 21 owners notice first.

Brooks Glycerin 23Men's at Amazon Women's

Availability last checked Sep 10, 2026. Prices and stock change without notice.

Glycerin 21 · 2023

Glycerin 23 · 2026

The two updates in between

Each step has its own page with the full change list and the verdict on that update.

Step 1Glycerin 21 to Glycerin 222025Changed character
Glycerin 21 vs 22 What replaced the Brooks Glycerin 21?
Step 2Glycerin 22 to Glycerin 232026Refined, same shoe
Glycerin 22 vs 23 What replaced the Brooks Glycerin 22?

Glycerin 21 vs Glycerin 23: every spec, side by side

The net of both updates. Per-update change notes stay on the step pages above, because they explain changes measured from a different starting point than this table uses.

Spec	Glycerin 21	Glycerin 23
FIT AND WEIGHT
Weight	9.8 oz	10.6 oz
Widths	D, 2E	D, 2E, 4E
Upper	Engineered warp knit	Triple-jacquard warp knit
CUSHIONING GEOMETRY
Heel stack	38 mm	38 mm
Forefoot stack	28 mm	30 mm
Drop	10 mm	8 mm
MATERIALS
Midsole	Nitrogen-infused DNA Loft v3	DNA Tuned supercritical foam
VALUE
List price at launch	$160	$175

Or buy the Glycerin 22 instead?

The Glycerin 22 is worth a look only if you want the ride it introduced, because that is the update that changed the shoe. Buying it to soften the jump does not work: you would be adapting to the same change either way, just at an older spec.

Buy the Glycerin 22

Stocked at Amazon

Men's: Check remaining stock Women's: Check price at Amazon

Availability last checked Sep 10, 2026.

Questions runners ask

Can I go straight from the Brooks Glycerin 21 to the Glycerin 23 and skip the Glycerin 22?: Yes, but going Glycerin 21 to Glycerin 23 means taking one change in a single step: the Glycerin 22 is where the ride moved. The drop also goes 10 mm to 8 mm across the jump, so give it a week of easy running.
How much did the weight change across these two updates?: 0.8 oz on in total, 9.8 oz to 10.6 oz in a men's US 9. The Glycerin 22 took it to 10.2 oz first.
Is the Glycerin 22 the better buy than either of these?: On paper it splits them: 10.2 oz against 9.8 oz for the Glycerin 21 and 10.6 oz for the Glycerin 23, on a 38 mm heel and a $165 list price. Whether that is worth chasing depends on what the Glycerin 22 update actually did, which the section above works through.
Did the Glycerin get taller between the Glycerin 21 and the Glycerin 23?: Heel stack went 38 mm to 38 mm, by way of 38 mm on the Glycerin 22. Drop moved 10 mm to 8 mm, which is the change your calves and Achilles notice.
Where does the Glycerin 23 sit in the Glycerin lineup now?: It is the current model, two versions on from the Glycerin 21 and the newest one you can buy at full retail.