Difference Wiki

Styrofoam vs. Polystyrene: What's the Difference?

Edited by Aimie Carlson || By Janet White || Updated on October 8, 2023
Styrofoam is a brand name for extruded polystyrene foam, while Polystyrene is a synthetic polymer made from styrene monomers.

Key Differences

Styrofoam and Polystyrene are terms often used interchangeably, but they have distinct meanings. Styrofoam is actually a trademarked brand name for a specific type of extruded polystyrene foam. Polystyrene, on the other hand, is a versatile plastic material made from styrene monomers, used in a variety of products.
Styrofoam, being a type of Polystyrene, possesses the lightweight, insulative properties of its base material. It's known for its blue color and is primarily used for building insulation and craft applications. Polystyrene, in its broader sense, can be found in a multitude of forms, ranging from hard plastics to foam products.
While Styrofoam refers specifically to a kind of foam insulation, Polystyrene can be categorized into various types, such as general-purpose polystyrene (GPPS) which is transparent and rigid, and high-impact polystyrene (HIPS), which is more durable and impact-resistant.
One major misconception is that disposable foam cups and containers are made of Styrofoam. In reality, these are made of expanded polystyrene (EPS) foam. Polystyrene's adaptability allows it to be molded into hard plastic products, like CD cases, or foamed for cushioning and insulation.
It's crucial to recognize the distinction between the brand name Styrofoam and the general material polystyrene to ensure appropriate use, recycling, and disposal. Polystyrene, in its various forms, has different recycling codes and processes, whereas Styrofoam requires specific recycling facilities.

Comparison Chart


Trademarked brand of extruded polystyrene foam.
Synthetic polymer made from styrene monomers.


Specific type of foam.
Varies from hard plastics to foams.

Primary Use

Building insulation, crafts.
Wide range, including containers, toys, packaging.

Relation to Branding

Specific brand name.
General material without brand-specific naming.

Common Misconceptions

Often wrongly associated with disposable foam products.
Broader category including various types of plastic/foam.

Styrofoam and Polystyrene Definitions


Recognizable by its blue color.
The blue Styrofoam is ideal for insulation.


A plastic material derived from styrene monomers.
The clear plastic case is made of Polystyrene.


Predominantly used for insulation.
Styrofoam panels keep the house warm in winter.


Often used in disposable containers.
These Polystyrene containers are lightweight and affordable.


A trademarked brand of extruded polystyrene foam.
I bought Styrofoam sheets for my craft project.


Can be molded into various forms.
They used Polystyrene to make that toy.


Requires specialized recycling.
This recycling facility doesn't accept Styrofoam.


Recyclable but varies by type and locality.
Check if your local facility accepts Polystyrene products.


Distinct from disposable foam cups.
Those aren't Styrofoam cups; they're made of EPS.


Found in hard plastics and foam products.
Polystyrene foam is used in packaging for its cushioning properties.


Expanded polystyrene foam, such as is used in cups and packaging.


A rigid clear thermoplastic polymer of styrene that can be molded into objects or made into a foam that is used as thermal insulation.


A light resilient foam of polystyrene


(organic chemistry) A vinylic polymer of styrene, CH2CHphenyl.


(organic chemistry) An alkane chain of benzene molecules, RCH2CHphenylR.


A polymer of styrene; a rigid transparent thermoplastic;
Expanded polystyrene looks like a rigid white foam and is used as packing or insulation


Is Styrofoam the same as Polystyrene?

No, Styrofoam is a specific type of Polystyrene foam.

What color is Styrofoam?

Traditionally, Styrofoam is blue.

What products are made from Polystyrene?

A range, from hard plastics like CD cases to foam products.

Is Styrofoam safe to use with food?

No, Styrofoam is not meant for food. EPS is used for food containers.

What is Styrofoam?

Styrofoam is a brand name for extruded polystyrene foam.

Are disposable cups made of Styrofoam?

No, they're usually made of expanded polystyrene (EPS).

Is Polystyrene recyclable?

Yes, but the process varies based on the type and local facilities.

Why is Styrofoam used for insulation?

Its properties provide good thermal resistance.

Is Polystyrene biodegradable?

No, it's a form of plastic and takes hundreds of years to decompose.

Why are Styrofoam and Polystyrene often confused?

Due to the generalization of the brand name for all foam products.
About Author
Written by
Janet White
Janet White has been an esteemed writer and blogger for Difference Wiki. Holding a Master's degree in Science and Medical Journalism from the prestigious Boston University, she has consistently demonstrated her expertise and passion for her field. When she's not immersed in her work, Janet relishes her time exercising, delving into a good book, and cherishing moments with friends and family.
Edited by
Aimie Carlson
Aimie Carlson, holding a master's degree in English literature, is a fervent English language enthusiast. She lends her writing talents to Difference Wiki, a prominent website that specializes in comparisons, offering readers insightful analyses that both captivate and inform.

Trending Comparisons

Popular Comparisons

New Comparisons