Introduction
PPI stands for Pixels Per Inch. It tells you how sharp a screen looks by measuring how many tiny dots (pixels) are packed into one inch of a display. A higher PPI means a sharper, clearer picture. This PPI calculator helps you find the pixel density of any screen in seconds. Just enter your screen's resolution (width and height in pixels) and its diagonal size in inches. The tool does the math for you and gives you the exact PPI number. This is useful when comparing monitors, phones, tablets, or TVs to see which one has a crisper display. Whether you are shopping for a new device or just curious about the screen you already own, this calculator makes it simple to figure out.
How to Use Our PPI Calculator
Enter your screen's resolution and size to find out its pixels per inch (PPI). PPI tells you how sharp and clear your display looks.
Horizontal Resolution (pixels): Type in the number of pixels your screen has going across. This is the first number in your resolution. For example, if your screen is 1920x1080, enter 1920 here.
Vertical Resolution (pixels): Type in the number of pixels your screen has going up and down. This is the second number in your resolution. Using the same example, you would enter 1080 here.
Screen Size (inches): Enter the diagonal size of your screen in inches. This is measured from one corner to the opposite corner. You can usually find this number in your device's specs or by measuring it yourself with a ruler or tape measure. If you need help figuring out the physical dimensions of your display, our Screen Size Calculator can help you convert between diagonal measurements, width, and height.
Once you fill in all three fields, the calculator will show you your screen's PPI. A higher PPI means your display has more pixels packed into each inch, which makes text, images, and videos look sharper. Most modern phones have a PPI above 300, while laptops and monitors typically range from 100 to 300 PPI.
What Is PPI (Pixels Per Inch)?
PPI stands for pixels per inch. It measures how many tiny dots (pixels) are packed into one inch of a screen. The higher the PPI, the sharper and clearer text, images, and videos will look on that display. PPI is one of the most important numbers to know when you are choosing a phone, tablet, laptop, monitor, or TV.
How Is PPI Calculated?
To find a screen's PPI, you need three pieces of information: the horizontal resolution (width in pixels), the vertical resolution (height in pixels), and the diagonal screen size (usually measured in inches). First, you calculate the diagonal resolution by using the Pythagorean theorem — take the square root of (width² + height²). Then you divide that diagonal pixel count by the diagonal screen size in inches. The result is the PPI.
Why Does PPI Matter?
A screen with a high PPI will display smoother edges on text and more detail in photos. A screen with a low PPI may look grainy or pixelated, especially when you sit close to it. This is why phones typically have much higher PPI values (often 400+) than TVs (often around 40–80 PPI) — you hold a phone inches from your face, but you sit several feet away from a TV.
Key Terms Explained
- PPcm (Pixels Per Centimeter): The same idea as PPI but measured in centimeters instead of inches. You get PPcm by dividing PPI by 2.54.
- Dot Pitch: The physical size of a single pixel, measured in millimeters. A smaller dot pitch means smaller pixels, which means a sharper image. Dot pitch is calculated as 25.4 divided by the PPI.
- Megapixels: The total number of pixels on the screen divided by one million. A 3840×2160 (4K) screen has about 8.3 megapixels.
- Aspect Ratio: The shape of the screen expressed as a ratio of width to height, such as 16:9 or 4:3. If you need to work with aspect ratios for scaling content or choosing a display, try our Aspect Ratio Calculator.
- Retina Display: A term Apple uses for screens where the pixel density is high enough that individual pixels cannot be seen at a normal viewing distance — generally around 300 PPI or higher for handheld devices.
PPI Density Ratings
Display pixel density is commonly grouped into ranges:
- Below 100 PPI: Low density. Common on large TVs. Text may look rough up close.
- 100–150 PPI: Standard density. Typical for desktop monitors at arm's length.
- 150–300 PPI: High density. Found on many laptops and tablets. Text and images look crisp.
- 300–500 PPI: Retina-level density. Common on modern smartphones. Individual pixels are invisible to the naked eye.
- Above 500 PPI: Ultra-high density. Found on premium phones and VR headsets.
Choosing the Right PPI for Your Needs
The "best" PPI depends on how you use the screen and how far away you sit. A 27-inch 4K monitor at 163 PPI looks very sharp on a desk. A 27-inch 1080p monitor at about 82 PPI will look noticeably less crisp at the same distance. For phones, anything above 300 PPI is generally considered excellent because you hold the device so close. For a living room TV viewed from 8–10 feet away, even 80 PPI can look perfectly fine because the viewing distance hides the individual pixels.
When comparing two screens of the same size, the one with higher resolution will always have a higher PPI. When comparing two screens with the same resolution, the smaller one will have a higher PPI. Use the comparison feature above to see exactly how different devices stack up side by side. If you're also interested in how much data your screen requires for streaming or downloading content at its native resolution, check out our Bandwidth Calculator and Download Time Calculator to plan accordingly.