The Ultimate Review of the Women’s Rab Infinity Alpine Jacket

Rab is recognised as one of the best outdoor brands for Down Insulation! So when my girlfriend was asking what jacket to get before we went to Iceland in the depths of Winter, I directed her to Rab Jackets. I own the Rab Microlight Alpine Down Jacket, which is a fantastic lightweight warm jacket, but not the best for seriously freezing temperatures. Whereas the Rab Infinity Alpine Jacket ticks the boxes and offers a great all-round jacket design for mountaineering use. Find out the key specs, strengths and considerations for this Women’s Down jacket as well as the alternatives and kit ratings.

Rab Infinity Alpine Jacket: Introduction

Key Specs

• Weight – 494g/17.4oz (Size S / 10)
• Outer Material- Zoned GORE-TEX INFINIUM™ Windstopper ® (30D & 15D)
• Inner Material- Lining 20D recycled nylon (38 g/m²) 
• Fill – 800FP European Goose Down
• Fit – Regular
• Price – £365.00 / $450

Overview

The Rab Infinity Alpine Women’s Jacket is a windproof down jacket that is exceptionally lightweight for this level of warmth and protection. With a close, regular fit, it excels on alpine-style, high-energy ascents in tough winter conditions. It’s built with two weights of windproof GORE-TEX INFINIUM™ WINDSTOPPER® technology: ultralight around the body to keep weight and bulk down, and heavier weight around the shoulders, upper body, and outer arms, for durability in rugged environments. Filled with 800FP down and designed to maximise mobility, it’s ideal for upward progress in wild winter weather. The sizing is true with my girlfriend (5ft 1″) opting for a Small for layering space.

Key Features

• 2 YKK® zipped hand pockets, 1 YKK® zipped internal chest pockets for added storage
• Highly compressible for stashing in a pack with a stuff sack included
• Minimally seamed overlay panel across upper body, shoulders and upper sleeve for added weather protection and reinforced fabrics for rugged terrain.
• Move freely with a refined fit and arm articulation.
• Harness-friendly two-way front zip with 2‑way YKK® Vislon front zip
• Zoned GORE-TEX INFINIUM™ WINDSTOPPER® fabrics: 30D (64gsm) & 13D (45gsm)., Lining 20D recycled nylon (38 g/m²) 
• Helmet-compatible hood seals out high winds.
• 800FP European goose down with Nikwax fluorocarbon-free hydrophobic finish (162g/ 5.7oz, Size 10).
• Optimised glove-fit with elasticated, adjustable cuffs.
• Minimises water ingress with interstitch baffle technology.

Rab Infinity Alpine Jacket: Strengths

• Exceptional Warmth-to-weight Ratio – The combination of 800 FP hydrophobic down (~162 g) and ultralight shell gives impressive warmth for less than 500 g – ideal for alpine ascents where weight matters. Plus, the use of Advanced stitch-through with “switch-back” overlapped baffles minimises cold spots.
• Weather Protection – GORE‑TEX INFINIUM WINDSTOPPER® is fully windproof to be water-resistant, and treated the fill-down with Nikwax hydrophobic treatment (RDS certified) to resist dampness and keep warmth in during light precipitation.
• Technical Design – Helmet-compatible hood with stiffened peak, articulated arms, and harness-friendly 2‑way zip make it mountaineering-ready and more suitable for climbing.
• Packability – Compressible down and lightweight shell allow packing into small backpack pockets—convenient for multi-day ventures 
• Ethical and Sustainable Materials – RDS-certified down, fluorocarbon-free finish, and recycled lining materials align with sustainable practices 
• Durability– Designed for mountaineering and climbing use, the Infinity Alpine uses a zoned Shell Fabric Zoned with GORE‑TEX INFINIUM™ WINDSTOPPER® technology. The combination of 30D & 13D patches means it adds robustness where needed and is lighter in other places.

Rab Infinity Alpine Jacket: Considerations

• Limited Wet-weather Performance – Despite being water-resistant, this jacket is not fully waterproof. The untreated seams eventually wet out under heavy rain. Best used as a belay jacket, not for continuous snow or soaked conditions.
• Sizing quirks– The regular fit is close fitting and for layering, it could be worth sizing up given it’s designed for cold weather use.
• Cuff Design – A small feature is that the elasticated cuffs are not as effective as Velcro or thumb loops in preventing wind or snow from sneaking inside the sleeve.
• Price – There are cheaper synthetic down jackets available for a lot less, but for the quality down that Rab is known for, the price is a premium. Additionally, the 800FP adds to this, rather than the 700FP found in the Microlight jackets. It’s an investment; however, discounts can be found.

Rab Infinity: Best Cases

This jacket is great for Fast, Alpine-style ascents when mountaineering or climbing, thanks to its warmth and water resistance. It’s perfect for cold and windy winter conditions, such as exposed snowy environments, due to the Windstopper technology. Finally, backpackers exploring cold climates who want a lightweight and packable insulation jacket, this is perfect, such as Scandinavia or Canadian weather.

On the other hand, if the weather is wet, then a waterproof hardshell on top would be required, not to weaken the down jacket’s effectiveness. Depending on the base and midlayers and if the temperature is below freezing, very low temperature belaying in severe conditions might not be suitable (see Neurtino Pro instead). It is bulkier than the Microlight and is less casual in style.

Alternatives

• Rab Infinity Microlight Down Jacket – Similar warmth but lighter fabric and slightly slimmer cut, ideal for those prioritising packability.
• Rab Microlight Alpine Jacket – Offers recycled materials and mapped baffles, slightly more casual yet still technical. See a full review of the Men’s Jacket here for more details.
• Rab Neutrino Pro Down Jacket – Warmer and heavier, for extremely cold, static use (e.g., long belays or basecamp). Arguably the best for technical and mountaineering use, with its top comfort on top.
• Patagonia Down Sweater™ Hoody –  lightweight and windproof with 800FP, with a similar price tag and super versatile. It has recycled material and is ethically sourced, too.
• Arc’teryx Cerium Jacket – Premium with 850FP Down Fill on the upper end, but lightweight, stylish and very versatile, more suitable for tough terrain and climates than the Patagonia (Neutrino competitor).

Kit Ratings

Final Thoughts

The Rab Women’s Infinity Alpine Down Jacket is a stand-out performer when technical warmth, lightness, and alpine-ready features are core priorities. Its excellent thermal performance, combined with thoughtful weather resistance and mountaineering-focused details, makes it a great choice for those serious about winter ascents. However, it doesn’t replace a hardshell for rain, and its price & tailored fit may not suit budget-conscious or casual users. Overall, the Rab Infinity Alpine Jacket is one of the best Women’s down jackets on the market and worthy of the investment in our opinion.

What is your favourite down jacket? Please comment and share this post with anyone looking for something to keep them warm in the cold!