August 11, 2026
The average poster board from a retail store is 22×28 inches. For advertising campaigns, the standard jumps to 24×36. Here’s what all common poster board sizes are used for and how to pick the right one.
We get questions about poster board sizes from two very different audiences. First: students, teachers, and hobbyists who need something to make a display or a project. Second: clients planning promotional campaigns who want to understand the print sizes they’re ordering.
The confusion happens because “poster board” means different things to each group. For the first group, poster board is the thick paper material sold in stacks at Walmart and Staples. For the second group, poster board is the physical format of a printed advertising piece. The sizes that matter for each group are different.
This guide covers both. We’ll start with the retail poster board sizes that students and hobbyists need, then move to the commercial print sizes that advertising clients care about.
These are the sizes you’ll find at major retail chains like Walmart, Target, Staples, and Michael’s:
| Size | Dimensions | Where You Find It | Common Use |
|---|---|---|---|
| Small | 14 x 22 in | Some Walmart and Target locations | Small projects, handmade signs |
| Standard / Average | 22 x 28 in | Universally available | School projects, event signs, displays |
| Large | 28 x 40 in | Larger craft and office stores | Larger displays, signs |
| Trifold (folded) | 16 x 48 in (folded) | All major retailers | Science fairs, presentations |
| Trifold (open) | 36 x 48 in (open) | All major retailers | Self-standing academic displays |
The 22×28 is the clear average and dominant size. It’s what most people mean when they say “poster board” without specifying a size. If a teacher assigns a project “on a poster board” without giving dimensions, assume 22×28.
The 22×28 size emerged from a combination of manufacturing conventions and practical utility. Paper manufacturers produced large sheets in multiples that could be efficiently cut to yield common sizes. The 22×28 yields cleanly from standard large sheet sizes. It’s also a comfortable size for hand-held display work: large enough to present information clearly, small enough to carry without difficulty.
The 22×28 also corresponds loosely to what the print industry calls a “half-sheet” or similar mid-format reference point. It fits comfortably on most table surfaces for school fair presentations. It’s a familiar size that students, teachers, and project participants can all work with intuitively.
Unlike the metric-based ISO system used in Europe, the 22×28 doesn’t come from a mathematical formula. It’s a practical size that evolved through retail convention and manufacturing efficiency. This is typical of US paper sizes generally, which developed independently from the metric system.
Quick reference: If someone asks for a “poster board” with no other specifications, get a 22×28. That’s the standard retail size. If they need something for advertising or commercial display, the conversation shifts to 18×24 or 24×36 printed pieces, which are different products entirely.
In advertising, the term “poster board” usually refers to a printed poster mounted on a stiff backing material. This is different from the blank craft-store poster board. The sizes that matter here are the standard advertising poster sizes:
| Commercial Poster Size | Dimensions | Common Use | Viewing Distance |
|---|---|---|---|
| Small Format | 11 x 17 in | Bulletin boards, indoor | Up to 10 feet |
| Standard Indoor | 18 x 24 in | Retail windows, venue interiors | 10 to 25 feet |
| Standard Outdoor | 24 x 36 in | Street campaigns, storefronts | 15 to 40 feet |
| Entertainment | 27 x 40 in | Cinema, major brand campaigns | Up to 30 feet |
| Large Outdoor | 36 x 48 in | Transit, large retail | 20 to 50 feet |
The “average” in commercial poster advertising is the 24×36. It’s the size that the industry clusters around for the majority of street-level campaign work. If someone in an advertising agency says “poster board,” they usually mean a 24×36 printed piece.
Poster board sizes matter, but so does the material. Here are the common material types and what they’re best suited for:
This is the material sold in packs at retail stores. It’s made from multiple layers of paper compressed and coated to create a stiff, smooth surface. It accepts markers, paint, and glue well. It’s not waterproof and will buckle if it gets wet. Weight is typically 100 to 160 grams per square meter. This is what most people mean when they say “poster board.”
Foam core has a foam inner layer between two thin paper facings. It’s much stiffer than paper poster board. It can be cut with a craft knife. It holds its shape much better than paper board. It’s more expensive. Used for professional display and presentation work. Comes in the same sizes as standard poster board, plus custom sizes.
Corrugated plastic is a lightweight, waterproof material used for outdoor signs and yard signs. It’s the most common material for political campaign signs and real estate signs. Available in standard sign sizes (18×24 and 24×36 are common). Not what people typically mean by “poster board” but frequently used for the same display purposes.
A commercially printed image laminated or dry-mounted to a rigid backing (foam core, PVC, or aluminum). This is the professional-grade product used in retail, trade shows, and branded display environments. Much more durable than craft store poster board. Sizes match standard advertising dimensions: 18×24, 24×36, etc.
The 22×28 single panel is the classic choice. Some competitions require or recommend a tri-fold, which opens to 36×48 and folds to about 16×48 for transport. Check your specific competition’s rules before buying materials.
Research presentations at academic conferences typically use a 36×48 portrait format. Trade show table displays often use a 24×36 or a tri-fold at 36×48. Larger trade show booth backdrops require custom sizes that go well beyond standard poster board dimensions.
For event signage that people carry or place on tables, the 22×28 craft-store poster board works well. For display signs around a venue, printed 18×24 or 24×36 is more appropriate. For exterior event signage, use a waterproof material at 24×36 or larger.
Retail poster displays almost always use commercially printed pieces on coated paper stock, mounted or in a snap frame. The standard retail poster size is 18×24 for interior displays and 24×36 for large window or exterior-facing placements.
Material matters as much as size: A 24×36 on 80 lb uncoated paper will look and behave differently from a 24×36 on mounted foam core. Think about both the size and the material when planning any poster project. The use case determines which combination is right.
For standard 22×28 retail poster board, go to Walmart, Target, Staples, Michael’s, or any major office or craft supply store. Multi-packs are available in white, black, and assorted colors at low cost.
For larger format or custom sizes, go to a print shop or sign company. FedEx Office, Staples Print, and independent large-format print shops all carry 18×24 and 24×36 as standard sizes. For mounted board products, specialty print vendors offer a range of substrates and sizes.
For advertising-quality poster boards (professionally printed, mounted, durable), work with a commercial print vendor who specializes in large-format printing. Turnaround times and minimum quantities vary, but most commercial printers can produce 18×24 and 24×36 in quantities from 25 to 1,000+.
Whether you are working with retail poster board or commercial advertising poster stock, setting up your design file correctly before production prevents costly reprints and color issues.
If you are creating a design to print and mount on a 22×28 poster board, set your design file at 22×28 inches at 300 DPI in CMYK color mode. If you are printing at home on a smaller sheet and then mounting it to the board, account for the bleed at the paper edges. A design printed on 8.5×11 sheets and tiled across the 22×28 board needs to account for the overlap or seam between sheets if that is the approach you are using.
Set up your file at the final trim size plus a 0.125-inch bleed on each side. A 24×36 poster file should be set at 24.25 x 36.25 inches. Resolution should be 150 DPI minimum for outdoor viewing distances. 300 DPI for indoor close-range viewing. Color mode must be CMYK. Export as PDF/X-1a or PDF/X-4 for professional print vendors.
Mounted poster boards are typically produced by printing the image on paper or vinyl and then laminating or adhering it to the rigid substrate. File setup is the same as for standard advertising poster sizes. The substrate choice affects the finish and durability but does not change the file requirements. Always ask your print vendor whether you need to add a die-cut line or router mark to the file if the mounted piece will be cut to a custom shape.
Understanding the difference between a poster board and a printed poster is essential for making the right purchase decision for any project.
A poster board from a craft store is a blank surface. You write on it, draw on it, or glue printed elements to it. It starts as raw material. You add content to create the finished piece. The 22×28 craft store board is this type of product.
A printed poster from a commercial print shop starts as a blank roll of paper or synthetic media. The printer applies your image to it using inkjet, laser, or offset technology. The result is a full-color, high-resolution finished piece that is ready to display. You may optionally mount it to a rigid backing for additional rigidity and durability.
In advertising and marketing contexts, when someone says they need a poster board for a campaign, they mean a printed poster, not a blank craft-store board. Knowing the distinction saves confusion in production and purchasing conversations with vendors and clients.
The average poster board size varies by the industry using it. Here’s how the 22×28 standard and its variants show up across different sectors.
In K-12 education, the 22×28 is the standard classroom project board. Elementary school students use it for book reports and science fair preparation. Middle and high school students use it for presentations and project displays. College students shift to larger formats (36×48) for research poster sessions and conference presentations. The 22×28 is so embedded in K-12 education that it’s simply called “the poster board” by most educators without specifying the dimensions.
The average poster board size for real estate yard signs and open house direction signs is 18×24, mounted on a wire stake or H-frame. Some markets use 24×36 as the standard for main property listing signs. Corrugated plastic (Coroplast) is the dominant substrate in this industry rather than traditional cardboard poster board, for its weather resistance.
Hotels, conference centers, and event venues use poster board displays for wayfinding, event schedules, and directional signage. The 22×28 format fits the lobby display stands that venues have installed as part of their permanent infrastructure. Hospitality displays in this size are typically printed rather than handwritten, mounted on foam core for a professional appearance in high-traffic public spaces.
Corporate offices use 22×28 for lobby and conference room informational displays: company values, organizational announcements, safety policies, and event notifications. In open office environments, 22×28 displays at workstation clusters or common areas communicate HR and operational information to employees without requiring permanent installation.
Non-profit organizations and community advocates use 22×28 for campaign signage, event promotion, and advocacy materials that need to be produced quickly and inexpensively by distributed volunteers. A community organizing campaign that needs 100 signs across a neighborhood in 48 hours can produce them using cardboard 22×28 boards from office supply stores with a standard printer and some planning, at a total cost of $150 to $300.
The 22×28 is the average, but it’s not always the right choice. Here’s a simple decision framework for selecting the right size.
The average size of a poster board at retail stores is 22×28 inches. This is the standard size sold in multi-packs at Walmart, Target, Staples, and craft stores. For advertising and commercial use, the standard shifts to 24×36 inches.
No. A 22×28 has 616 square inches. A 24×36 has 864 square inches. The 24×36 is approximately 40% larger in area and larger in both dimensions. They’re different products for different uses.
For most school projects, the standard 22×28 inch poster board works well. For science fair displays that need to stand on their own, a 36×48 tri-fold is the most common choice. Always check your specific assignment or competition guidelines for size requirements.
The most common poster board size at Walmart is 22×28 inches, sold in white, black, and color packs. Some locations also carry tri-fold boards at 36×48. The 22×28 is the dominant size in Walmart’s school and craft supply section.
Standard retail poster board is typically 14 to 16 point thick (about 0.36 to 0.41 mm). This is significantly stiffer than standard paper but not as rigid as foam core. Foam core boards are typically 3/16 inch (about 4.8 mm) thick, which is roughly 10 times the thickness of standard poster board.
Standard display frames and snap frames come in sizes that match print advertising sizes, not craft-store poster board sizes. The most common snap frame size is 18×24. The 22×28 retail poster board doesn’t fit a standard 18×24 frame cleanly. If you need to frame a poster board project, measure the board and get a custom frame.
The average tri-fold poster board measures 36 inches wide by 48 inches tall when open. When folded, the two side panels close over the center panel, making the folded size approximately 16 inches wide by 48 inches tall. Dimensions vary slightly by brand.
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