On
Core Running Jacket
The On Core Running Jacket is a lightweight, windproof, stretch running jacket made from recycled polyamide and polyester with a Durable Water Repellency finish. It features a full-length zip, adjustable hood, storm flaps for ventilation, zipped pockets, raglan sleeves, articulated elbows, reflective details, and folds into a carry pouch for portability. User reviews recommend it for winter running, noting it meets all requirements for cold-weather protection while maintaining full range of motion.
- Material
- Recycled polyamide and polyester
- Gender
- unisex
- Style
- sporty, performance, technical
- Category
- Apparel & Accessories > Clothing > Activewear
Color
Size
Specifications
Versatile lightweight running jacket with windproof stretch fabric, designed for weather-ready activewear.
Windproof stretch fabric, DWR treatment, adjustable hood, storm flaps, raglan sleeves, packable design, reflective details.
- Material
- Recycled polyamide and polyester
- Secondary
- polyester
- Style
- sporty, performance, technical
- Occasion
- workout, hiking, travel
- Gender
- unisex
- Age Group
- adult
- Condition
- new
- Category
- Apparel & Accessories > Clothing > Activewear
Additional Attributes
- lightweight windproof stretch fabric
- made of recycled polyamide and polyester
- Durable Water Repellency (DWR) treatment
- full-length front zip
- built-in adjustable hood
- storm flaps at front and back for ventilation
- zipped pockets
- raglan sleeves with articulated elbows for range of motion
- packable into small carry pouch
- adjustable toggle hem
- reflective details for visibility in low light
- versatile design for various weather conditions
Product Insights
The On Core Running Jacket is a 159g windproof knit shell that packs into its own pocket to grapefruit size mid-run, trading heavy downpour protection for breathable wind-blocking, adjustable ventilation, and a stretchy athletic fit that moves freely over layers. Its recycled polyamide fabric resists wet-out from light rain and avoids membrane delamination, while reflective trim and a secure hem drawcord make it a purposeful cold-weather layer that sheds heat when needed.
- Mid-run stow
Packs into its own pocket in one motion, even mid-run.
Why this is supported
The packable front pocket enables a single-motion pack-down. As brand copy explains,
When the weather gets warmer, no one wants to spend their time lugging around a jacket. This packable front pocket solves that problem quickly and easily so you can get on-the-go even quicker.
on.comThis means you can stow the jacket without breaking stride, redeploying it on windy stretches or as temperature drops.
- Packed size
Compresses to grapefruit size (5x5 in sphere) without permanent creasing.
Why this is supported
When packed into its own front pocket, the jacket compresses small—
when packed into its carry pouch it compresses to about the size of a grapefruit (roughly 5" x 5" sphere).
What is the approximate weight of the jacket, and how small does it pack when folded into its pouch?The 13% elastane in the main fabric provides the stretch needed to achieve that compression without permanent creasing, as confirmed by the fabric composition:
87% Recycled Polyamide, 13% Elastane
fleetfeet.com.
- Weight
Weighs 159g, 10–20g lighter than shells with separate stuff sacks.
Why this is supported
The Core Jacket uses a DWR-treated knit fabric that is windproof and breathable, achieving a weight of 159g without adding a heavy waterproof membrane. This design choice automatically skips the 10–20g penalty of a separate stuff sack, as the front pocket doubles as the carry pouch. As described, it is
a design choice that prioritizes weight savings and packability over heavy-rain protection.
Actual weight and how it compares — water_repellent_classificationAnd independent analysis notes:
making the Core one of the most weight-efficient packable running shells available.
How the packable design works in practice — zero_added_pouch_weight- Packability
Packs to a 5-inch sphere and stows in one motion into its front pocket.
Why this is supported
When packed into its front pocket, the Core Jacket compresses to a grapefruit-sized sphere,
when packed into its carry pouch it compresses to about the size of a grapefruit (roughly 5" x 5" sphere).
What is the approximate weight of the jacket, and how small does it pack when folded into its pouch?The knit construction allows it
to compress to its grapefruit size without permanent creasing
How the packable design works in practice — knit_construction_with_elastaneMoreover, the integrated pouch enables
single-motion pack-down that doesn't require digging out a detached pouch
How the packable design works in practice — mid_run_quick_stowmaking it practical for mid-run stow.
- Windproof knit
Tightly-knit fabric blocks wind yet remains breathable and stretchy.
Why this is supported
The light, protective knit material is designed to provide extra wind protection while remaining breathable.
The light, protective knit material gives you extra wind protection during your run. Plus, it's still breathable so you won't be trapping in the sweat.
on.comHowever, the fabric prioritizes weather protection over maximum breathability, making it better for cold-weather runs. The fabric contains 13% elastane and uses a spiral dart construction to provide stretch and movement.
The fabric is windproof and DWR-treated, which prioritizes weather protection over maximum breathability—reviewers recommend it for winter running, indicating it's better suited for cold conditions.
How breathable is the fabric during high-intensity running? Does the storm flap ventilation help significantly?The composition and construction details are confirmed:
Main Fabric: 87% Recycled Polyamide, 13% Elastane
therunhub.ieA unique spiral dart construction allows for movability
on.comAs a result, buyers recommend this jacket for winter running.
Seconded - it's not cheap but the Core jacket from On hits all of these requirements.
u/picatone in r/runningfashion- Ventilation control
Adjustable storm flaps and drawcord let you control airflow.
Why this is supported
The jacket features front and back storm flaps that cover the zipper and rear vent, allowing the runner to open the closure for ventilation without compromising wind protection.
The storm flaps at the front and back do provide adjustable ventilation to help manage heat during high-intensity efforts
How breathable is the fabric during high-intensity running? Does the storm flap ventilation help significantly?Additionally, the adjustable drawcord at the hood and hem enables the runner to cinch tight against drafts or loosen for heat release.
Thanks to water-repellent material and an adjustable drawstring on the hood and the hem, you can keep the rain and cold firmly at bay.
on.com- DWR
DWR sheds light rain and prevents wet-out, but not heavy downpours.
Why this is supported
This jacket’s DWR is designed for light rain and drizzle. It prevents the fabric from wetting out, which is critical because
Wet skin cools down up to twenty-five times faster than dry skin.
runnersneed.comHowever, it is not sufficient for heavy downpours, as
The Durable Water Repellency (DWR) treatment on this jacket is designed to shed light rain and drizzle, not to withstand heavy downpours.
Is the DWR treatment on this jacket sufficient for heavy rain, or is it only for light drizzle?- Wind protection
Windproof knit with adjustable hem/hood seals out drafts; storm flaps allow ventilation without wind entry.
Why this is supported
On describes the jacket as windproof, and the brand states the knit material
The light, protective knit material gives you extra wind protection during your run. Plus, it's still breathable so you won't be trapping in the sweat.
on.comThe adjustable drawstring on the hood and hem further seals wind, as noted:
an adjustable drawstring on the hood and the hem, you can keep the rain and cold firmly at bay.
on.comStorm flaps cover the front zipper and back vent, enabling incremental ventilation without wind entry, ensuring the jacket adapts to changing intensity during a run.
- Water resistance
DWR treatment beads water to prevent fabric wetting and heat loss; can be heat-reactivated.
Why this is supported
Gore-Tex explains the DWR mechanism:
Similarly, an effective DWR treatment keeps water droplets at a high contact angle with the fabric of the rainwear. This minimizes the surface area of the wetted fabric and better allows water droplets to roll off.
gore-tex.comThis keeps the fabric dry, crucial because
Wet skin cools down up to twenty-five times faster than dry skin.
runnersneed.comWhen the treatment degrades, it can be restored by heat reactivation:
Once it is dry, tumble dry your garment for 20 minutes to reactivate the durable water-repellent (DWR) treatment on the outer fabric.
gore-tex.comOn classifies the jacket as water-repellent for light rain and snow, not sustained heavy precipitation.
- Visibility
Reflective elements improve visibility in low-light winter runs.
Why this is supported
Product images and description show reflective trim on the chest flap and a reflective tab on the back vent, which enhance visibility during the short daylight hours of winter running. This addresses a key safety concern for runners training before sunrise or after sunset.
- Range of motion
Spiral dart construction prevents across-the-back pull during arm swing.
Why this is supported
The spiral dart construction uses a curved three-dimensional seam that rotates with the torso, eliminating the across-the-back pull that limits arm swing in straight-seam jackets.
A unique spiral dart construction allows for movability
on.comRaglan sleeves extend from collar to underarm in a single diagonal seam, removing shoulder binding, and articulated elbows are pre-shaped to prevent fabric bunching at the inner elbow. The jacket's main fabric contains 13% elastane, giving it notable stretch and allowing the jacket to move with the body without restricting rotation or arm reach, even over a thick mid-layer. This combination of design elements provides more range of motion than the slim fit of elite racing shells.
- Hem drawcord
Adjustable hem drawcord cinches the jacket securely to the hips.
Why this is supported
The adjustable toggle hem cinches the jacket securely to the hips, preventing it from riding up and bunching during arm and torso movement, ensuring that the ergonomic features remain effective.
- Breathability
Knit fabric blocks wind yet breathes; storm flaps and drawcords release heat incrementally.
Why this is supported
The knit material is windproof yet breathable:
The light, protective knit material gives you extra wind protection during your run. Plus, it's still breathable so you won't be trapping in the sweat.
on.comStorm flaps provide adjustable ventilation for high-intensity efforts,
allowing incremental ventilation without sacrificing wind protection
Windproof performance and real-world protection — storm_flap_zipper_barriersand drawcords can be loosened to release heat during tempo changes.
tightening them seals out drafts and traps a warm air layer, while loosening them releases heat during tempo changes
Windproof performance and real-world protection — drawcord_adjustable_hood_and_hem- Temperature range
Best for cold winter runs; packs into its pocket to shed mid-run when heat builds.
Why this is supported
The jacket is optimized for winter running; Q&A notes that
for warm-weather running you may find it traps heat.
How breathable is the fabric during high-intensity running? Does the storm flap ventilation help significantly?The packable design supports a start-warm-then-stash strategy:
Stuffing into its own front pocket is a single-motion pack-down that doesn't require digging out a detached pouch—ideal when the weather shifts mid-run and you need to shed a layer without breaking stride.
How the packable design works in practice — mid_run_quick_stow- Hem adjustability
Adjustable hem drawcord cinches the jacket tightly to hips to prevent riding up.
Why this is supported
On's website notes that
an adjustable drawstring on the hood and the hem, you can keep the rain and cold firmly at bay
on.com, which directly supports the ability to cinch the hem to prevent riding up over layers.
- Recycled content
87-95% recycled polyamide, waste-derived, throughout the jacket.
Why this is supported
Multiple sources confirm the recycled polyamide percentages:
Main Fabric Composition: 87% Recycled Polyamide, 13% Elastane
fleetfeet.com,
Secondary Fabric Composition: 92% Recycled Polyamide, 8% Elastane
fleetfeet.com, and
Lining Composition: 95% Recycled Polyamide, 5% Elastane
fleetfeet.com. This waste-derived nylon
directly reducing demand for virgin petroleum and diverting plastic waste from oceans or landfills
Recycled polyamide construction and its benefits — 87_95_recycled_polyamide_throughout.
- Fabric durability
The knit fabric construction avoids membrane delamination.
Why this is supported
The jacket's windproofing comes from its knit fabric construction, not a laminated membrane.
On classifies the Core Jacket as water-repellent rather than waterproof, meaning it relies on a lightweight DWR-treated knit fabric without a three-layer membrane — a design choice that prioritizes weight savings and packability over heavy-rain protection.
Actual weight and how it compares — water_repellent_classificationThis avoids the membrane delamination that can degrade multi-layer shells over time. Additionally, the elastane content helps the fabric recover shape after compression:
The main fabric’s 13% elastane content and light knit construction—unlike stiffer ripstop—allow the jacket to compress to its grapefruit size without permanent creasing and to regain shape quickly
How the packable design works in practice — knit_construction_with_elastaneAnd it packs into its own front pocket, removing the need for a separate stuff sack that can be lost or torn:
packs into its own front pocket
fleetfeet.com- Reflective details
Reflective trim on chest, rear vent, and sleeves provides 360-degree visibility.
Why this is supported
The jacket integrates reflective elements across three key areas: the chest overlay carries a curved reflective trim, the rear vent flap has a reflective tab, and the forearms have small reflective dots, providing visibility from all sides.
Integrated reflective elements boost visibility during the shorter, darker days of winter when many runs happen in low-light conditions
Suitability for winter running and layering — reflective_details_for_low_light_safetyThis 360-degree coverage eliminates blind spots for approaching traffic, enhancing safety during dark runs.
- Athletic design
Packs into its own pocket, moves freely, and layers over a base layer.
Why this is supported
The jacket
packs into its own front pocket
fleetfeet.comand
when packed into its carry pouch it compresses to about the size of a grapefruit
What is the approximate weight of the jacket, and how small does it pack when folded into its pouch?. It uses
A unique spiral dart construction allows for movability
on.comand offers
a regular, athletic fit that accommodates light layering
How does the Core Running Jacket fit compared to other On jackets? Is it slim or regular fit?.
- Materials and reputation
Manufactured from 87-95% recycled polyamide; endorsed by Reddit users.
Why this is supported
The main fabric is
87% Recycled Polyamide, 13% Elastane
fleetfeet.com. A Reddit user confirmed the jacket's value:
Seconded - it's not cheap but the Core jacket from On hits all of these requirements.
u/picatone in r/runningfashion- Self-stowing
Self-stows into its front pocket; DWR maintains packability in light rain.
Why this is supported
The Core jacket
packs into its own front pocket
fleetfeet.com, enabling a 'warm-up then stash' tactic mid-run. The DWR treatment
is designed to shed light rain and drizzle
Is the DWR treatment on this jacket sufficient for heavy rain, or is it only for light drizzle?, preventing wet-out that would ruin packability. Runners confirm it
hits all of these requirements
u/picatone in r/runningfashion. This self-stowing design allows multiple deploy-and-stow cycles during variable conditions.
- Pack size
Weighs 159g and packs to grapefruit size; compresses without creasing.
Why this is supported
The jacket
weighs approximately 5.6 oz (159 g) for a men's medium, and when packed into its carry pouch it compresses to about the size of a grapefruit (roughly 5" x 5" sphere).
What is the approximate weight of the jacket, and how small does it pack when folded into its pouch?. The 13% elastane in the main fabric enables repeated compression without permanent creasing, keeping the jacket looking new after many pack/unpack cycles.
- Temperature regulation
Adjustable storm flaps and drawstrings let you seal or release warmth mid-run.
Why this is supported
The storm flaps
provide adjustable ventilation to help manage heat during high-intensity efforts
How breathable is the fabric during high-intensity running? Does the storm flap ventilation help significantly?. The adjustable drawstring on the hood and hem allows sealing or releasing warmth, and the knit material
gives you extra wind protection during your run
on.comwhile staying breathable. Together, these enable responsive temperature control during the warm-up and active phases.
- Layering fit
Raglan sleeves and 13% elastane stretch comfortably over thick mid-layers.
Why this is supported
The spiral dart construction
allows for movability
on.com, and the 13% elastane in the main fabric (
Main Fabric: 87% Recycled Polyamide, 13% Elastane
therunhub.ie) stretches comfortably over thick winter mid-layers, ensuring the jacket doesn't restrict arm drive during runs.
Image Analysis
3 images- 01
Product
Right-side view of a black lightweight running jacket with an attached hood, high collar, chest overlay flap with a short reflective trim, zippered side pocket, elasticated cuffs, and a small white brand logo near the lower hem.
- Hood and collarAttached hood with a high collar that extends to cover the neck; hood appears unstructured and lies flat against the upper back and shoulder.
1 region
x 0.26 · y 0.06 · w 0.41 · h 0.21 (high) - Chest overlay flapHorizontal overlay panel across the upper chest with a short angled reflective strip on the right edge of the flap.
1 region
x 0.47 · y 0.33 · w 0.32 · h 0.18 (high) - Side zip pocketVertical zippered side pocket with a visible zipper pull tab located on the right side seam under the chest flap.
1 region
x 0.48 · y 0.49 · w 0.14 · h 0.18 (high) - Sleeve constructionLong raglan-style sleeve with visible sleeve seam lines and slightly gathered elastic at the wrist cuff.
1 region
x 0.03 · y 0.23 · w 0.58 · h 0.42 (medium) - Lower-hem logo“Small white stylized brand logo printed near the lower left hem area.”
1 region
x 0.04 · y 0.79 · w 0.14 · h 0.14 (high) - Fabric appearanceMain body and sleeves show a matte, lightly textured synthetic fabric; upper overlay appears slightly smoother and more wind-resistant.
Other
Studio product shot showing a model in motion against a neutral light background; image crops the top of the head and shows strong frontal lighting with soft shadows.
- Model pose and cropModel shown in right-side running pose with right arm raised; top of the head is cropped out of frame.
1 region
x 0.56 · y 0.00 · w 0.43 · h 0.32 (high) - Sunglasses propModel wears large wrap sunglasses with an orange mirrored lens and clear frame visible on the face.
1 region
x 0.68 · y 0.03 · w 0.26 · h 0.17 (high) - Background and lightingUniform pale neutral background with soft, even studio lighting and minimal shadows; slight shadow fall visible at lower left of the frame.
Colors
matte black· main body and sleeves#0E0C0Flight reflective gray· chest overlay reflective trimwhite· lower-hem logo- Hood and collarAttached hood with a high collar that extends to cover the neck; hood appears unstructured and lies flat against the upper back and shoulder.
- 02
Product
Front view of a lightweight black running jacket worn by a model; central full-length zipper, attached hood, short reflective curved trim across the upper torso, and a small white chest logo on the wearer's left side.
- Overall shapeWaist-length jacket with a straight hem, raglan sleeves, and an attached close-fitting hood visible at the neck and back of the head.
1 region
x 0.16 · y 0.13 · w 0.68 · h 0.66 (high) - Center zipperBlack full-length front zipper runs from the hem to the chin, aligned with the jacket center front.
1 region
x 0.47 · y 0.18 · w 0.06 · h 0.60 (high) - Upper chest flap and reflective trimA horizontal upper-chest overlay or flap extends across the front and ends with a narrow white reflective piping detail that curves downward toward the sides.
3 regions
x 0.22 · y 0.30 · w 0.56 · h 0.18 (high); x 0.33 · y 0.37 · w 0.10 · h 0.04 (high); x 0.57 · y 0.37 · w 0.10 · h 0.04 (high) - Chest logoSmall white stylized logo on the wearer's left chest area.
1 region
x 0.58 · y 0.26 · w 0.06 · h 0.08 (high) - Side pockets (zip seams)Vertical side pockets indicated by faint seam lines running near the jacket side panels, aligned with the lower torso.Partial
2 regions
x 0.20 · y 0.46 · w 0.12 · h 0.30 (medium); x 0.68 · y 0.46 · w 0.12 · h 0.30 (medium) - Sleeve cuffSimple narrow hem at the sleeve ends with no visible elastic or fastener.
2 regions
x 0.15 · y 0.68 · w 0.14 · h 0.12 (high); x 0.71 · y 0.68 · w 0.14 · h 0.12 (high) - Fabric appearanceSmooth, slightly matte woven fabric on the upper panels with a subtler textured look on the lower torso panels, suggesting two fabric panels.
1 region
x 0.24 · y 0.20 · w 0.52 · h 0.40 (high) - Legible text - logo“on”
1 region
x 0.58 · y 0.26 · w 0.06 · h 0.08 (high)
Other
Studio front-facing shot of a model wearing the jacket against a plain light gray background; model holds a neutral pose and wears mirrored sports sunglasses and black shorts. Even soft lighting with minimal shadows; image cropped slightly above the knees.
- Shot compositionCentered, straight-on front view of a standing model captured from head to upper thighs.
1 region
x 0.00 · y 0.00 · w 1.00 · h 1.00 (high) - BackgroundUniform light gray seamless background with no visible props or scenery.
- Model accessoriesThe model is wearing large mirrored wrap sunglasses with a multicolored reflective lens.
1 region
x 0.36 · y 0.02 · w 0.28 · h 0.12 (high) - Lighting and shadowSoft, even studio lighting with minimal directional shadows under the chin and arms.
Colors
deep black· main body#0E0D0Ewhite· logowhite reflective· reflective piping- Overall shapeWaist-length jacket with a straight hem, raglan sleeves, and an attached close-fitting hood visible at the neck and back of the head.
- 03
Product
Rear view of a black running jacket on a model showing an attached hood, a horizontal rear vent flap with a small reflective tab, long raglan sleeves with elastic cuffs, and a small light-colored logo near the lower right back.
- Hood shapeFolded attached hood with rounded top and visible seam lines, sitting against the upper back and neck.
1 region
x 0.32 · y 0.06 · w 0.36 · h 0.18 (high) - Rear vent flapHorizontal cape-like vent flap across the upper back ending slightly above mid-back, with a narrow exposed gap under the flap.
1 region
x 0.18 · y 0.28 · w 0.64 · h 0.20 (high) - Reflective tab on flapSmall rectangular light-colored reflective tab centered on the lower edge of the rear vent flap.
1 region
x 0.46 · y 0.38 · w 0.08 · h 0.04 (high) - Lower back logoSmall light-colored vertically oriented two-character logo or mark printed near the lower right back hem.
1 region
x 0.72 · y 0.70 · w 0.08 · h 0.12 (high) - Sleeve constructionLong raglan sleeves with visible seam lines running from neck to underarm; sleeves narrow toward elastic cuffs at the wrists.
2 regions
x 0.02 · y 0.24 · w 0.22 · h 0.56 (high); x 0.78 · y 0.24 · w 0.20 · h 0.56 (high) - Reflective sleeve accentsSmall light-colored reflective dots or short marks visible on each sleeve near the forearm area.
2 regions
x 0.12 · y 0.52 · w 0.04 · h 0.06 (medium); x 0.84 · y 0.52 · w 0.03 · h 0.06 (medium) - Hem and back panelLower back panel continues below the vent flap to a slightly curved hem that falls to the top of the hips.
1 region
x 0.18 · y 0.48 · w 0.64 · h 0.38 (high)
Other
Studio rear-shot of a model wearing the jacket against a plain light background; even soft lighting with minimal shadows; model wears sunglasses and black shorts which are not part of the product.
- Shot compositionCentered rear-facing medium-full shot showing the jacket from the top of the hood to the upper thighs of the model.
- BackgroundEven light gray studio background with no props or patterns.
- Model and stylingMale model shown from behind wearing clear-frame sunglasses and black shorts; hands visible at sides.
- Lighting and reflectionsSoft even lighting with slight specular highlights on the jacket fabric indicating a smooth, slightly shiny surface on the upper panels.
Colors
deep black· upper panels and hood#0E0D11deep black· lower back panel and sleeves#0E0C0Flight gray reflective· reflective trim and logo- Hood shapeFolded attached hood with rounded top and visible seam lines, sitting against the upper back and neck.
Documents & Data
Reddit Insights
1 threads · r/runningfashionThe On Core jacket is recommended as meeting all requirements for a hooded winter running jacket, though noted as expensive.
The single mention is a recommendation, with a minor caveat about cost.
Themes
Use Cases
- Winter running jacket
Watch Out For
Source Threads
On Core jacket recommended as meeting requirements
Seconded - it's not cheap but the Core jacket from On hits all of these requirements.
u/picatoner/runningfashionView thread →