Glycerin 21
Previous-generation plush Brooks daily trainer, often available at a discount vs Glycerin 22.
Available in Men's and Women's sizing.
- Max Cushion
- Neutral
- Maximum
- 10mm Drop
- 283g
- Best forSoft ride.
- Runner typeNeutral gait
- SurfacesRoad
Overview
Previous-generation plush Brooks daily trainer, often available at a discount vs Glycerin 22.
Kitletics notes particular strengths around soft ride and value when discounted.
- Soft ride
- Value when discounted
Kitletics Review · 7.0 Solid
Brooks Glycerin 21 is a max-cushion daily trainer. Previous-generation plush Brooks daily trainer, often available at a discount vs Glycerin 22. I'd shortlist it for soft ride. The trade-off is superseded by Glycerin 22 — Brooks Glycerin 22 is the cleaner compare when that is most of your week. It fits buyers who actually need a max-cushion daily trainer, not a one-product rotation.
Read Kitletics Review →At a glance
- Weight
- 283 g
- Drop
- 10 mm
- Heel Stack
- 38 mm
- Cushioning
- Maximum
- Stability
- Neutral
- Terrain
- Road
- Plate
- No
- Category
- Running Shoes
- Best for
- Soft ride
Pros & cons
Pros
- Soft ride
- Value when discounted
Cons
- Superseded by Glycerin 22
Kitletics Review
A buying decision based on structured product data and evidence — not invented star ratings or fake user reviews.
Kitletics Review
Verdict
Brooks Glycerin 21 is a max-cushion daily trainer. Previous-generation plush Brooks daily trainer, often available at a discount vs Glycerin 22. I'd shortlist it for soft ride. The trade-off is superseded by Glycerin 22 — Brooks Glycerin 22 is the cleaner compare when that is most of your week. It fits buyers who actually need a max-cushion daily trainer, not a one-product rotation.
Pros
- maximum cushioning for the sessions it was built for
- Width options include narrow, standard, wide, extra-wide
Cons / Trade-offs
- Not designed for technical trail terrain
Best for
- Soft ride.
- Plush ride that still fits max-cushion daily trainer sessions.
- Neutral max-cushion daily trainer.
- Value when discounted.
Not ideal for
- Those looking for superseded by Glycerin 22.
- Those looking for a lightweight race-day shoe.
- Those looking for Brooks Glycerin 22 when a max-cushion daily trainer is not the weekly job.
How it performs
What it is
Previous-generation plush Brooks daily trainer, often available at a discount vs Glycerin 22. Brooks Glycerin 21 is built for a specific job in the category — use that job as your first filter. I'd shortlist it when you want soft ride or value when discounted. Skip it if.…
Key specs
Here are the numbers that matter for the Brooks Glycerin 21: • Weight: 283 g • Drop: 10 mm • Heel Stack: 38 mm • Forefoot Stack: 28 mm • Cushion Level: maximum • Stability: neutral • Terrain: road • Width Options: narrow, standard, wide, extra-wide • Plate: No • Plate Material:.…
Where it is strongest
I'd buy the Brooks Glycerin 21 when these outcomes match what you need most weeks: What it does well • Soft ride • Value when discounted The standout is soft ride. If that is your main weekly need, keep going. If not, check trade-offs and alternatives. Best for: You want soft.…
Trade-offs & limits
The Brooks Glycerin 21 is not trying to do every job. These are the compromises to weigh: • Superseded by Glycerin 22 Skip it if: You need to avoid superseded by Glycerin 22 — forcing the Glycerin 21 into that job usually disappoints. Those limits matter when they hit your.…
Key specs that matter
| Spec | Value | Why it matters |
|---|---|---|
| Weight | 283 g | Affects how lively or protective the shoe feels on easy miles. |
| Drop | 10 mm | Influences stance and load distribution — preference, not a quality score. |
| Heel Stack | 38 mm | Contributes to cushion depth under the heel on landings. |
| Forefoot Stack | 28 mm | Affects forefoot protection and how the toe-off feels. |
| Stability | Neutral | Indicates guidance geometry versus a pure neutral ride. |
| Terrain | Road | Defines primary surface suitability (road, trail, mixed). |
| Width Options | Narrow, Standard, Wide, Extra Wide | Official widths available — separate from subjective toe-box feel. |
Should you buy it?
Buy if
- You're looking for soft ride.
- You want a plush ride that still fits max-cushion daily trainer sessions.
- You prefer a neutral max-cushion daily trainer.
- You want value when discounted.
Skip if
- You need to avoid superseded by Glycerin 22.
- You're primarily looking for the lightest race-day option.
- You prefer Brooks Glycerin 22 when a max-cushion daily trainer is not the weekly job.
- You prefer superseded by Glycerin 22.
Final verdict
Brooks Glycerin 21 is a max-cushion daily trainer. Previous-generation plush Brooks daily trainer, often available at a discount vs Glycerin 22. I'd shortlist it for soft ride. The trade-off is superseded by Glycerin 22 — Brooks Glycerin 22 is the cleaner compare when that is most of your week. It fits buyers who actually need a max-cushion daily trainer, not a one-product rotation.
Alternatives to consider
BrooksGlycerin 22Why choose this instead: Want a premium option?
8.3 · GoodFrom € 170Compare →
NikeInvincible 3Why choose this instead: Want better value?
7.2 · SolidFrom € 190Compare →
ASICSNovablast 5Why choose this instead: Want better value?
8.8 · Very GoodFrom € 130Compare →
How we assessed it
How we assessed the Brooks Glycerin 21: this is Expert Research. We used manufacturer specifications (283 weight, 10 mm drop), the published role as a max-cushion daily trainer, and a comparison set (Glycerin 22, Novablast 5, Invincible 3). We have not personally tested this product. Feel claims and scores are research-informed, not a wear diary.
Review type: Expert Research Review.
Read how we review products →
Specifications
- Weight
- 283g
- Drop
- 10mm
- Heel Stack
- 38mm
- Cushioning
- Maximum
- Stability
- Neutral
- Terrain
- Road
- Plate
- No
Geometry
| Weight | 283 g |
|---|---|
| Heel Stack | 38 mm |
| Forefoot Stack | 28 mm |
| Drop | 10 mm |
Ride
| Cushioning | Maximum |
|---|---|
| Cushion Feel | Plush |
| Stability | Neutral |
Construction
| Plate | No |
|---|---|
| Plate Material | None |
Use
| Terrain | Road |
|---|---|
| Training Types | Easy, Long, Recovery |
Fit
| Width Options | Narrow, Standard, Wide, Extra Wide |
|---|
Other
| Fit / Sizing | Men, Women |
|---|
Where to buy
Showing offers for Netherlands. Prices may change at the retailer.
Brooks Official
in stockBrand DirectNLLast checked 12 September 2026€ 140Check priceAmazon.nl
in stockMarketplaceNLLast checked 12 September 2026€ 140View on Amazon
Kitletics may earn a commission when you buy through some retailer links. This does not affect our recommendations. Affiliate disclosure
Sources & evidence
Transparency behind this Kitletics Review — not a substitute for the buying decision above.
Verified specification
Official product specifications
Used to verify identity, published measurements, materials and official features.
Verified 12 September 2026
Editorial research
Independent expert reviews & Kitletics editorial analysis
Used to cross-check ride, fit, category placement and buying trade-offs. Not a Kitletics personal wear-test.
Verified 12 September 2026
Running Shoe Finder
Find shoes that match your running, goals, fit preferences and budget.
Shoe Rotation Planner
Plan a shoe rotation around your training — coverage, gaps and what to add next.
Running Pace Calculator
Calculate pace, finish time and distance with race splits.
Product data verified 12 September 2026. Prices checked 12 September 2026.
Independent & Transparent
We don't sell gear. Guidance is independent, labelled honestly, and evidence-led.
Always Up to Date
Products, prices and new releases are continually reviewed.
Real Prices
Regional retailer offers with last-checked timestamps — not invented MSRP.
Find What Fits You
Smart tools match gear to your sport, goals and budget.