Imagery: AI-generated. People depicted are not real individuals.
In this guide: how each heated layer is meant to fit, and why the vest sizes differently from the hoodie.
EarthBae Core, the heated hoodie, is true to size.
EarthBae Heat, the heated vest, is cut with a little room and works better worn close, so if you are between two sizes, take the smaller one.
That is the whole decision.
Why the heated vest sizes down
EarthBae Heat is a slim technical shell. Its warmth comes from engineered composite heating elements in three zones, two across the chest and one across the back.
Those zones work best against you. Worn loose, there is a layer of air between the elements and your body, and the vest spends its energy warming that air first.
A heated car seat behaves the same way. Sit on it and you feel it immediately. Hover an inch above it and you barely do.
Worn close, the heat has nowhere to go but into you.
Why the heated hoodie does not
EarthBae Core is a heavyweight fleece hoodie, and the fabric itself holds warmth around your body. The heating elements are working inside a layer that is already insulating.
That changes what the fit needs to do.
Core is cut relaxed on purpose, and the weight of the fleece does the work a snug fit would have to do in a thinner garment.
Order it the way you would order any hoodie you plan to wear as an outer layer.
What to wear underneath
A thin base layer under the vest. Heavy fleece underneath sits between the elements and your skin and slows the heat reaching you.
Core and Heat are both built to be your outer layer in cool to cold weather. A heavy coat goes over the top only in genuinely extreme cold.
The short version
Core, your usual size. Heat, your usual size, or the smaller one if you are between.
Size charts are on each product page.
One decision, and only on the vest.
Related Reading
Heated Apparel: The Complete Guide - How heated apparel works, what to look for, and how to choose.
What Is Active Thermal Regulation? - The category EarthBae is building, and what makes a layer active.
The 7.4V Battery Standard - Runtime, charging, and why one battery powers the whole line.
Published July 27, 2026