Quick answer: What is resolution DPI? DPI stands for dots per inch and describes how many dots a printer lays down across one inch of paper. It is often used loosely to mean PPI, pixels per inch, which describes how densely an image’s pixels are packed when displayed or printed at a given physical size. Resolution itself is the total number of pixels in an image, such as 3000 by 2400. DPI or PPI only becomes meaningful when you attach a physical size to those pixels: a 3000-pixel-wide image printed 10 inches wide is 300 PPI, which is the standard for sharp prints. On screen, DPI is irrelevant; only the pixel count matters.
Few terms in digital art cause as much confusion as resolution and DPI, partly because software uses them interchangeably when they mean different things, and partly because the number that matters changes depending on whether the work is headed for a screen or a printer. An artist can spend hours worrying about a DPI setting that has no effect on their final export, or discover too late that a canvas with plenty of DPI has far too few pixels for the poster they wanted.
This explainer separates the three ideas, resolution, PPI, and DPI, shows how they relate with a few simple calculations, and then applies them to digital painting, printing, scanning, and photography. For readers setting up a canvas for digital work, the companion guide to the best resolution for digital painting turns these principles into specific canvas sizes.
Three Terms, Three Meanings
Resolution: how many pixels
In digital imaging, resolution most precisely means the pixel dimensions of an image: its width and height counted in pixels. A 1920 by 1080 image has 1920 columns and 1080 rows, or about 2.07 million pixels. A 6000 by 4000 photo has 24 million pixels. This number is fixed when the image is created and only changes if the image is resampled, which either invents new pixels (upscaling) or discards existing ones (downscaling).
Pixel count is the true measure of how much detail an image contains. Everything else is a way of describing how those pixels are spread over physical space.
PPI: pixels per inch
PPI describes density: how many of an image’s pixels fall within one inch when the image is displayed or printed at a particular size. It is a relationship between pixel count and physical dimensions, not an inherent property of the image. The same 3000-pixel-wide image is 300 PPI when printed 10 inches wide, 150 PPI when printed 20 inches wide, and 75 PPI when printed 40 inches wide. Nothing about the file changed; only the size you chose to print it at.
The PPI value stored in an image file is just a note to software suggesting a default print size. Changing it without resampling does not alter a single pixel.
DPI: dots per inch
DPI is a printer specification. Inkjet and laser printers build an image out of tiny ink or toner dots, and DPI describes how many of those dots the hardware can place per inch. A typical inkjet is rated at 1200, 2400, or 4800 DPI. Those dots are not pixels; a printer uses many dots of a few ink colors to reproduce the color of a single pixel, through a process called halftoning or dithering. So a 300 PPI image printed on a 2400 DPI printer uses roughly 8 by 8 printer dots per image pixel.
In everyday use, and in most software dialogs, “DPI” is used to mean PPI. When Procreate, Photoshop, or a print shop asks for 300 DPI, they mean 300 pixels per inch at the final print size. This article uses DPI in that common sense from here on, while keeping the distinction in mind.
The Relationship in One Formula
Pixels = inches × DPI, and therefore DPI = pixels ÷ inches, and inches = pixels ÷ DPI.
| Pixel width | Printed at 300 DPI | Printed at 150 DPI | Printed at 72 DPI |
|---|---|---|---|
| 1200 px | 4 inches | 8 inches | 16.7 inches |
| 2400 px | 8 inches | 16 inches | 33.3 inches |
| 3600 px | 12 inches | 24 inches | 50 inches |
| 6000 px | 20 inches | 40 inches | 83.3 inches |
Reading across a row shows why DPI alone means nothing: the same pixels make a sharp small print or a soft large one. Reading down a column shows how many pixels you need for a given print size at a given quality.
What DPI Do You Actually Need?
The right density depends on how close the viewer will be.
- 300 DPI is the standard for prints viewed at arm’s length: art prints, photo books, greeting cards, magazine pages. At this density individual pixels are invisible to most viewers.
- 240 DPI is often indistinguishable from 300 on matte and textured papers, which soften detail anyway. Many fine art printers accept 240 as a floor.
- 150 to 200 DPI suits large posters and canvas prints viewed from a few feet away. Canvas texture hides the lower density.
- 100 DPI or less is normal for banners, billboards, and murals viewed from across a room or a street.
- Above 300 DPI brings diminishing returns for most work. Very fine line art and small text can benefit from 400 to 600, but photographs and paintings rarely show a difference.
The practical rule: decide the largest size you might ever print, multiply by 300, and make the canvas at least that many pixels. It is easy to downscale later and impossible to add real detail by upscaling.
DPI and Screens: Why 72 Is a Myth
A persistent piece of advice says web images should be 72 DPI. This dates from early Macintosh monitors that displayed roughly 72 pixels per inch, so a 72 DPI image appeared at its print size on screen. Modern displays range from about 100 PPI on a budget monitor to over 450 PPI on a phone, and browsers and apps ignore the DPI tag entirely. A 1200 by 800 pixel image displays identically whether its file says 72, 300, or 1 DPI.
For anything shown on a screen, only pixel dimensions matter. Export at the pixel size the destination needs and disregard the DPI field.
What Is Resolution in Photography?
In photography, resolution usually refers to the sensor’s pixel count, expressed in megapixels. A 24-megapixel camera produces images around 6000 by 4000 pixels. That pixel count determines the largest sharp print: 6000 pixels at 300 DPI is 20 inches wide, and at 200 DPI it is 30 inches.
Photographers also use “resolution” to describe the lens-and-sensor system’s ability to resolve fine detail, measured in line pairs per millimeter, which is a different concept. A high-megapixel sensor behind a soft lens delivers lots of pixels but little real detail. For artists using photos as references or printing their own photography, the megapixel count is the number to work from, with the understanding that image sharpness depends on focus, lens quality, and camera shake as well.
What Is Resolution in a Computer or Monitor?
Display resolution is the pixel grid a monitor shows: 1920 by 1080 (Full HD), 2560 by 1440 (QHD), 3840 by 2160 (4K UHD), and so on. Monitor PPI is that pixel count divided by the screen’s physical width. A 27-inch 4K monitor is about 163 PPI; a 27-inch 1080p monitor is about 82 PPI. Higher PPI means smaller pixels and a smoother image at the same viewing distance.
For digital painters, display resolution affects how much of a large canvas is visible at 100 percent zoom and how fine the on-screen rendering looks, but it has no effect on the resolution of the artwork itself. A 6000-pixel-wide painting is 6000 pixels wide whether it is viewed on a 1080p or 4K monitor. Operating systems also use the terms “scaling” or “display scaling” to make interface elements larger on high-PPI screens, which can confuse matters further; that scaling changes how big things look, not how many pixels a file has.
Applying DPI to Digital Painting
When a painting app asks for a canvas size, it typically offers width, height, and DPI. Here is how to think about those fields.
- Decide the final physical size you want to be able to print, say 16 by 20 inches.
- Multiply by 300 to get the pixel dimensions: 4800 by 6000 pixels.
- Set the DPI field to 300 so the file carries the intended print size as metadata. This does not change the pixels; it just tells print software the default size.
- Check the layer limit. Apps like Procreate reduce available layers as pixel count rises. If the limit is too tight, drop to 240 DPI (3840 by 4800) rather than shrinking the print size.
- Paint at that size. Zooming in to work on detail is fine; the pixels are there.
- Export for screen by resizing down to the pixel dimensions the platform wants, ignoring DPI.
- Export for print at full pixel size as TIFF, PNG, or high-quality JPEG with the DPI tag set so the printer software reads the right dimensions.
Scanning Traditional Art: DPI That Actually Means Dots
Scanners are one place where DPI is used in its original hardware sense, meaning samples per inch of the original. Scanning an 8 by 10 inch watercolor at 300 DPI yields 2400 by 3000 pixels, enough to print at the same size at full quality. Scanning at 600 DPI yields 4800 by 6000, enough to print at double size at 300 DPI or to crop in on details.
Rules of thumb for scanning artwork:
- 300 DPI to reproduce at the same size.
- 600 DPI to enlarge up to 2x or to allow heavy cropping.
- 1200 DPI only for very small originals, such as miniatures or stamps, that will be enlarged substantially.
- Higher than needed wastes storage and scanning time with no visible gain.
Resampling: The Only Way DPI Changes Pixels
Image editors offer a resize dialog with a “resample” checkbox. With resampling off, changing DPI simply rewrites the metadata and adjusts the stated print size; the pixel count is untouched. With resampling on, changing DPI or print size tells the software to add or remove pixels.
Downsampling (reducing pixels) is generally safe and often improves sharpness slightly by averaging detail.
Upsampling (adding pixels) interpolates new pixels from existing ones. Modern algorithms, including AI-based upscalers, can produce convincing results for moderate enlargements of about 1.5x to 2x, especially on painted or illustrated work. They cannot recover detail that was never captured, and text, hard edges, and fine texture degrade first. Treat upsampling as a rescue, not a plan.
Common Misunderstandings
“My image is 300 DPI so it will print sharp.” Only at or below the size its pixel count supports. A 1200-pixel-wide image at 300 DPI prints sharp at 4 inches and soft at 12.
“Changing the DPI to 300 fixed my low-resolution image.” Without resampling, nothing changed except metadata. With resampling, pixels were interpolated and the image is larger but no more detailed.
“Web images must be 72 DPI.” Browsers ignore DPI. Pixel dimensions are all that matter on screen.
“A 4800 DPI printer needs 4800 DPI images.” Printer DPI counts ink dots, not pixels. 300 PPI images are the standard input for any consumer or fine art printer.
“Higher DPI is always better.” Past about 300 PPI at viewing distance, extra pixels increase file size and reduce available layers with no visible improvement.
FAQs
Is DPI the same as resolution?
No. Resolution is the pixel count of an image. DPI (or more accurately PPI) is how densely those pixels are packed per inch at a given physical size. An image has one resolution but can be printed at many DPI values depending on how large you make it.
What is the difference between DPI and PPI?
PPI is pixels per inch, a property of an image displayed or printed at a given size. DPI is dots per inch, a printer’s hardware spec describing ink dots. In common usage, including most software, DPI is used to mean PPI.
What DPI should I use for printing artwork?
300 DPI at the final print size is the standard for prints viewed up close. 240 is acceptable on textured papers, and 150 to 200 works for large canvases and posters viewed from a distance.
Does DPI matter for images on a screen?
No. Screens and web browsers display images by pixel dimensions and ignore the DPI metadata. Export at the pixel size the platform requires.
What is resolution in photography?
Usually the sensor’s pixel count in megapixels, which sets the largest sharp print size. A 24-megapixel image around 6000 by 4000 pixels prints at 20 by 13 inches at 300 DPI.
What is resolution in a computer monitor?
The pixel grid the display shows, such as 1920 by 1080 or 3840 by 2160. Dividing that by the screen’s physical width gives its PPI. Monitor resolution affects how your artwork looks on screen but not the resolution of the artwork file.
Final Thoughts
Resolution is pixels, DPI is pixels per inch at a chosen size, and printer DPI is a hardware spec that mostly takes care of itself. Start every project from the largest print you can imagine wanting, multiply by 300 to get the pixel count, and the DPI question answers itself. Specific canvas sizes for different kinds of digital painting, and how they balance detail against layer limits and performance, are laid out in the guide to choosing the right resolution for digital painting, which builds directly on the formula explained here.
