Every image you send to a printer is one of two kinds: raster or vector. On a laptop screen you often cannot tell them apart. On a wall, the difference is obvious. A raster file is a grid of colored pixels. A vector file is a set of instructions for drawing shapes. Blow both up to eight feet tall, and only one of them is guaranteed to stay sharp.
This guide explains how each file type works, how each one behaves when it is printed at wall size, the pros and cons of both, and which to use for your project. If you only want the short version, start with the table below.
The Short Answer
| If your artwork is... | It is usually... | What to send |
|---|---|---|
| A photograph, scan, painting, or AI-generated image | Raster | The largest original file you have (JPG, PNG, TIFF, HEIC, or WebP) |
| A logo, line illustration, or lettering | Vector | The original AI, EPS, SVG, or PDF, not a screenshot of it |
| A repeat pattern | Either | Vector if you have it. Otherwise a very large, seamless raster tile |
| A mix of photo and graphics | Both | A PDF with the photo embedded at full resolution, or send the pieces separately |
What Is a Raster File?
A raster file (also called a bitmap) is a rectangular grid of tiny squares called pixels. Each pixel holds one color, and together they form the image. Photos from a camera or phone, scans, digital paintings made in Photoshop or Procreate, screenshots, and AI-generated images are all raster files. Common formats include JPG, PNG, TIFF, HEIC, and WebP.
Characteristics of raster files
- A fixed number of pixels. A file that is 6000 x 4000 pixels contains exactly that much information, no matter how large you print it.
- Resolution dependent. The more pixels you spread across a given width, the sharper the print. The fewer, the softer it looks.
- Rich in detail. Raster handles photographic texture, soft gradients, shadows, and subtle color changes better than any other format.
- File size grows with pixels. A wall-size raster file can run to hundreds of megabytes.
How raster files print
The printer needs enough pixels to cover your wall at a good pixels-per-inch (ppi) count. If there are too few, each pixel gets stretched across a larger area. Depending on how the file is enlarged, that shows up as visible blocks, jagged edges, or a general softness, as in the comparison below.
One common point of confusion: the DPI number saved in a file's settings does not change how many pixels it contains. A 1,000-pixel-wide image labeled "300 DPI" is still a 1,000-pixel-wide image. What matters is the pixel dimensions, and how large you want to print them.
Raster pros and cons
Pros: excellent for photographs and realistic imagery; captures subtle color and texture; supported by every camera, phone, and editing app; easy to share.
Cons: loses sharpness when enlarged beyond its pixel count; wall-size files are large; compressed formats like JPG lose detail each time they are re-saved; screenshots and messaging apps compress images further.
What Is a Vector File?
A vector file does not store pixels at all. It stores shapes, defined by points, lines, and curves, along with the colors that fill them. Logos, icons, typography, line illustrations, and many repeat patterns are made this way in programs like Adobe Illustrator, Affinity Designer, or Inkscape. Common formats include AI, EPS, SVG, and PDF.
Characteristics of vector files
- Resolution independent. A vector logo is the same file whether it ends up on a business card or a lobby wall.
- Small file size. Shapes take far less space to describe than millions of pixels.
- Crisp edges and clean color. Flat color areas and sharp lines stay exactly that, at any scale.
- Easy to edit. You can recolor a shape, resize a pattern, or change a line weight without degrading anything.
How vector files print
Every digital printer ultimately places tiny dots of ink. Before printing, the printer's software (called a RIP) converts the file into those dots at the final size. With a vector file, that conversion happens fresh at the size you choose, so edges are drawn sharp whether the artwork is 2 feet or 20 feet wide. With a raster file, the dots can only be built from the pixels you supplied.
A vector file can still contain a raster image inside it. If a logo file includes an embedded low-resolution photo, that photo will be exactly as sharp as it was to begin with, no matter how crisp the surrounding shapes are.
Vector pros and cons
Pros: scales to any wall size without losing sharpness; tiny files that are easy to send; ideal for logos, lettering, line art, and geometric or repeat patterns; simple to recolor and resize.
Cons: poorly suited to photographs and painterly textures; needs vector software to create or edit; text must be converted to outlines or the wrong font may be substituted; effects like shadows and blurs are sometimes flattened into pixels on export.
Raster vs. Vector at a Glance
| Raster | Vector | |
|---|---|---|
| Built from | Pixels in a grid | Mathematical shapes and curves |
| Best for | Photos, scans, paintings, realistic detail | Logos, lettering, line art, patterns |
| When enlarged | Gets soft or blocky once pixels run out | Stays sharp at any size |
| File size | Grows with pixel count, often very large for walls | Small, regardless of print size |
| Common formats | JPG, PNG, TIFF, HEIC, WebP, PSD | AI, EPS, SVG, PDF |
| Main risk on a wall | Not enough pixels for the size | Missing fonts, flattened effects, or a hidden low-res image |
Why Size Matters More on a Wall
A photo that looks perfect on a screen or as a 5 x 7 print can fall short on a full wall, because the same pixels are stretched across many more inches. Our FAQ recommends 150 to 300 pixels per inch at full wall size for the best results. Here is what that means in practice.
| Wall size (W x H) | Pixels needed at 150 ppi | Effective ppi from a 24-megapixel photo (6000 x 4000) |
|---|---|---|
| 8'0" x 8'0" | 14,400 x 14,400 | About 42 ppi |
| 10'0" x 8'0" | 18,000 x 14,400 | About 42 ppi |
| 14'0" x 9'0" | 25,200 x 16,200 | About 36 ppi |
In other words, very few files reach 150 ppi on a full wall, even from a professional camera. That does not mean the photo cannot be printed. Details that look soft at arm's length tend to disappear from across a room, and atmospheric images such as skies, water, foliage, and textures are more forgiving than sharp architectural detail or text. Upscaling software can also help. But the more real pixels you start with, the less is left to chance, and anything with fine lines or lettering is better supplied as vector.
Not sure what your wall measures? Our guide on how to measure your walls for custom wallpaper walks through it step by step.
Which File Type Should You Use?
Photo murals
Landscapes, cityscapes, family photos, and other photographs are raster. Use the original file straight from the camera or phone, at full size and with the highest quality setting, rather than a copy that has been resized or compressed.
Repeat patterns
Patterns are where vector shines, because a vector pattern can be printed at any repeat size without softening. Many of the patterns in our catalog start as vector artwork for exactly this reason. If you are bringing your own pattern, send the vector file if you have one. If it is raster, make the tile as large as you can and make sure the edges repeat seamlessly.
Logos and graphics for commercial spaces
Lobby walls, feature walls, and branded environments often combine a logo or lettering with other artwork. Always send the original vector logo (AI, EPS, SVG, or PDF) rather than a copy saved as a JPG or pulled from a website. For project-scale work, see our commercial wallcovering page.
Illustrated and hand-painted murals
It depends on how the artwork was made. If it was drawn in vector software, send the vector file. If it was painted by hand and scanned, or created in a raster app such as Procreate or Photoshop, treat it as raster and make the canvas as large as your software allows before you start.
Common File Mistakes (and How to Avoid Them)
Sending a screenshot or a text-message copy
Screenshots capture only the pixels on your screen, and messaging apps compress images to save data. Upload the original photo file instead.
Raising the DPI to fix a small file
Changing the DPI value in an editor does not add pixels. The pixel dimensions are what count.
Saving a vector logo as a JPG, then sending the JPG
Exporting to JPG turns shapes into pixels at one fixed size. Keep and send the original vector file.
Leaving fonts unconverted
If a vector file uses a font that is not embedded or outlined, it may be replaced with a different one. Convert text to outlines before you save, or send the font along with the file.
Expecting screen colors to match ink exactly
Screens glow and ink reflects, so very bright or neon colors can look different in print. If a particular brand color matters, tell us the Pantone or color value, and consider ordering a sample of your own artwork on the material you plan to use. A custom design sample lets you check color and sharpness before you commit to the full wall.
A Quick File Prep Checklist
- Start with the original file, never a screenshot, a copy sent by text, or a version saved from a website.
- Know your wall size in feet and inches so you can judge how many pixels you need.
- For photos and other raster art, use the largest, highest-quality version you have.
- For logos, lettering, and patterns, send vector (AI, EPS, SVG, or PDF) whenever you have it.
- Convert text to outlines in vector files, and keep any embedded photos at full resolution.
- Check your file against the sizes in the table above, then upload it or send it to us for review.
Frequently Asked Questions
What is the difference between a raster and a vector file?
A raster file is a grid of colored pixels, like a photo. A vector file is a set of mathematical shapes and curves, like a logo drawn in Illustrator. Raster files have a fixed number of pixels and soften or blur when enlarged too far. Vector files can be scaled to any size and the edges are redrawn sharp each time.
What resolution do I need to print a wall mural?
What counts is the number of pixels in the file, not the DPI number in its settings. For the best result, aim for 150 to 300 pixels per inch at the full size of your wall. Very few files reach that on a large wall, and a big wall viewed from across a room is more forgiving than a small print viewed up close. Our team reviews every file and tells you if it is too small or low quality.
Can I just enlarge a small image to make it fit my wall?
You can make the file larger, but resizing in an editor or raising the DPI setting does not add real detail. The software estimates the new pixels, which can smooth things out but cannot recover what was never captured. Start from the largest original you have, and order a sample to check the sharpness on the material.
Is a PDF a raster or a vector file?
Either, or both. A PDF is a container. It can hold vector shapes, raster images, or a mix. A PDF exported from a vector design stays sharp at any size, while a PDF made from a screenshot or a photo is still just pixels.
Can I convert a raster image to a vector?
Sometimes. Tracing tools can turn a flat-color logo or simple line drawing into vector shapes, though the result usually needs cleanup. Photographs and images with soft gradients do not convert well, because a vector version would need an enormous number of shapes to imitate every pixel.
What file types can I upload for custom wallpaper?
The upload tool on our custom wallpaper page accepts JPG, PNG, HEIC, WebP, TIFF, and PDF files up to 1GB. If your artwork is an AI, EPS, or PSD file, send it to us and we will take care of it.
Ready to Print Your Own Artwork?
Upload your file on our custom wallpaper page and preview it on your wall before you order. If you are unsure whether your file is big enough, or you are working with an AI, EPS, or PSD file, send it to us and we will take a look. Every file is reviewed, and we will let you know if it needs attention before it goes to print.
