The short answer
Cardboard and paper are closely related but not exactly the same thing. Both are made mainly from cellulose fibers, usually from wood, that are pulped, formed into a sheet and dried. Cardboard is a heavier, thicker, stiffer material, and some kinds are built from several layers. Paper is the thinner, lighter, more flexible relative. There is no single universal line between them, and the boundary is defined a little differently by different industries and countries.
What paper and cardboard have in common
- Raw material. Both are typically made from plant fiber, most often wood pulp, though other fibers such as textile or grass fibers can be added. Recycled fiber is widely used for both.
- Basic process. Fibers are mixed with water, spread into a thin mat, pressed and dried. If you want to see this process in action for a thin product, read how tissue paper is made.
- Recyclability. Both are generally collected and recycled together in many places, though local rules differ.
How they differ
Thickness and weight. Cardboard is thicker and heavier per sheet. Paper weight is measured in grams per square meter (gsm) or in pounds in the US. Papers that are heavy enough, such as cardstock, start to feel like thin board, so the two materials overlap. Many sources treat sheets above roughly 160 gsm as card, but this is a rule of thumb rather than a strict standard. For more on heavier craft sheets, see our guide to craft paper types.
Structure. Paper is typically a single thin layer. Cardboard can be:
- Solid board, a thick single sheet or several thin layers pressed together, like the board in a cereal box.
- Corrugated board, made from a wavy middle layer between flat sheets, like shipping boxes. The wave-shaped layer adds stiffness and cushioning. You can follow the details in the process of making cardboard.
Strength and use. Paper is for writing, printing, wrapping and folding. Cardboard is for packaging, protection and structure. Boxes that must carry weight need long, strong fibers, which is one reason a recycling system still needs some new fiber added over time.
Finish. Paper may be coated, sized or bleached for brightness and printing. Cardboard is often left unbleached and brown, though some board has a white or coated outer layer for printing.
What is cardboard really called?
“Cardboard” is an everyday word, and industry uses more specific names:
- Paperboard or boxboard, for thinner, flat board such as cereal and tissue boxes.
- Corrugated fiberboard (or corrugated board), for shipping boxes with a wavy layer inside.
- Containerboard, the materials used to make corrugated boxes.
- Card or cardstock, for heavier paper used in crafts and stationery.
So the question “what is cardboard?” usually has a simple answer: a thick, stiff, paper-based material used for packaging and structure.
Cardboard vs a box
A box is an object, while cardboard is the material it is often made from. A box can also be made from other materials such as wood, plastic or metal, and cardboard can be used to make things other than boxes, such as tubes, dividers, displays and craft projects.
Recycling: the same bin?
In many areas, clean paper and clean cardboard are collected together in the same recycling stream, but rules vary by town and country, so check your local guidelines.
Items that are commonly not accepted or are treated differently include:
- Paper or board heavily soiled with grease or food, such as a very greasy pizza box.
- Paper that is wet, moldy or contaminated.
- Items coated or laminated with plastic or wax, or lined with foil, such as some drink cartons and takeout cups, which may be handled in a separate stream or not accepted at all.
- Used tissues, paper towels and similar sanitary paper, which are usually not recycled.
Flatten boxes and remove tape or plastic where your local program asks you to. Fibers can only be recycled a limited number of times, because they get shorter and weaker with each cycle, so fresh fiber is still needed. Recycled content can also make packaging slightly thicker for the same strength.
Craft uses
Both are staples of paper crafting. Paper is better for folding, cutting fine detail and layering. Thin cardboard suits card bases, templates, boxes, models and stencils. Corrugated cardboard is useful for sturdy projects like organizers and play structures. If you are building from a recycled box, check the fold lines, cut with a fresh blade, and expect to need a strong glue or tape.
Safety
- Thick cardboard is harder to cut. Use a sharp blade, cut slowly on a cutting mat, and never push hard toward your hand.
- Keep craft knives and scissors out of reach of small children, and supervise older children.
- Use glue, spray adhesive and paint as directed on the label, with ventilation where advised.
- Cardboard dust and small cut-off pieces can be a nuisance and a choking hazard for toddlers and pets.
FAQ
Is cardboard just thick paper? Roughly, yes, though many cardboards have a layered or corrugated structure that paper does not.
Can cardboard be made into paper? In recycling, cardboard fibers can be pulped and used again for paper or board products, depending on the quality of the fiber.
Is cardstock paper or cardboard? It sits in between. It is a heavy paper, and thicker types are close to thin board.