Ppi Calculator
Free PPI calculator to find pixels per inch for any display. Calculate screen density, DPI, dot pitch for monitors, TVs, phones & tablets. Compare display quality instantly.
Enter Display Specifications
PPI Comparison Chart
Compare pixel density across popular devices to understand display quality differences:
| Device | PPI | Category | Density Bar |
|---|---|---|---|
| iPhone 15 Pro Max | 460 | Retina | |
| Samsung Galaxy S24 Ultra | 505 | Retina | |
| iPad Pro 12.9" | 264 | High | |
| MacBook Pro 14" M3 | 254 | High | |
| 27" 4K Monitor | 163 | Medium | |
| 27" QHD Monitor | 109 | Standard | |
| 24" FHD Monitor | 92 | Standard | |
| 32" 4K Monitor | 138 | Medium | |
| 55" 4K TV | 80 | Low | |
| 65" 4K TV | 68 | Low |
Display Density Categories
Retina / Ultra High (300+ PPI)
Individual pixels invisible to naked eye. Found in smartphones and premium tablets.
High Density (200-299 PPI)
Excellent clarity for laptops and high-end monitors. Apple calls this "Retina".
Medium Density (150-199 PPI)
Good quality for 4K monitors at 27-32 inches. Some pixelation if viewed closely.
Standard Density (100-149 PPI)
Typical for office monitors. Acceptable from normal viewing distances.
Low Density (Below 100 PPI)
Large TVs viewed from distance. Individual pixels may be visible up close.
How to Calculate PPI
What is PPI?
PPI (Pixels Per Inch) measures the pixel density of a screen. Higher PPI means more pixels packed into each inch, resulting in sharper images and text. PPI is also known as pixel density or screen resolution density.
The PPI Formula
Step 1: Calculate diagonal in pixels using Pythagorean theorem:
Diagonal Pixels = √(Width² + Height²)Step 2: Divide by diagonal screen size:
PPI = Diagonal Pixels ÷ Diagonal InchesExample Calculation
For a 24-inch 1920×1080 monitor:
• Diagonal pixels = √(1920² + 1080²) = √(3,686,400 + 1,166,400) = √4,852,800 = 2203 pixels
• PPI = 2203 ÷ 24 = 91.8 PPI
What is Dot Pitch?
Dot pitch is the distance between pixel centers, measured in millimeters. It's the inverse of PPI:Dot Pitch = 25.4 ÷ PPI
Lower dot pitch means higher density and sharper image.
PPI vs DPI: What's the Difference?
PPI (Pixels Per Inch)
- • Measures screen pixel density
- • Used for displays, monitors, phones
- • Fixed by hardware - cannot be changed
- • Determines visual sharpness of display
DPI (Dots Per Inch)
- • Measures print dot density
- • Used for printers, scanners, images
- • Can be adjusted in software/settings
- • Determines print quality resolution
Note: For screens, PPI and DPI are often used interchangeably since one pixel equals one dot. The distinction matters primarily for printing where a single pixel might be rendered using multiple ink dots.
Frequently Asked Questions
What is a good PPI for a monitor?
For desktop monitors, 90-110 PPI is standard, 110-140 PPI is good, and 140+ PPI is excellent. Apple considers 200+ PPI as "Retina" quality where individual pixels become invisible at normal viewing distance.
What PPI is 4K at 27 inches?
A 27-inch 4K (3840×2160) monitor has approximately 163 PPI. This is considered medium-high density, offering noticeably sharper text and images compared to a 27" 1440p monitor (109 PPI) or 27" 1080p monitor (82 PPI).
What is Apple Retina display PPI?
Apple's Retina displays vary by device: iPhone 15 Pro has 460 PPI, MacBook Pro 14" has 254 PPI, and iMac 27" has 218 PPI. "Retina" means the pixel density is high enough that individual pixels can't be distinguished at typical viewing distance.
Why do phones have higher PPI than monitors?
Phones are viewed much closer (10-12 inches) than monitors (20-30 inches). Higher PPI is needed for screens viewed close-up to appear sharp. A 100 PPI monitor viewed at 24 inches looks similar in sharpness to a 400 PPI phone viewed at 6 inches.
Does higher PPI mean better display?
Not necessarily. PPI is one factor in display quality. Color accuracy, contrast ratio, brightness, response time, and panel type (IPS, OLED, VA) also matter significantly. A 100 PPI OLED can look better than a 150 PPI TN panel.
What PPI do I need for photo editing?
For professional photo editing, aim for at least 100-110 PPI. Many professionals prefer 4K monitors at 27-32 inches (120-163 PPI) for a good balance of screen real estate and detail visibility. Some prefer 5K displays for even higher density.
Is 1080p on a 24-inch monitor good enough?
A 24" 1080p monitor has ~92 PPI, which is standard density. It's acceptable for general use, gaming, and productivity. For sharper text and detailed work, consider 1440p at 24" (~122 PPI) or 27" 4K (~163 PPI).
What is dot pitch and why does it matter?
Dot pitch is the physical distance between pixel centers in millimeters. Lower dot pitch = higher density = sharper image. A 0.28mm dot pitch (~91 PPI) is standard; 0.18mm (~141 PPI) is high quality; below 0.1mm is Retina-class.
Related Calculators
This calculator provides accurate PPI calculations based on screen specifications. Actual perceived sharpness may vary based on viewing distance and individual vision.