Image Resolution Calculator
Calculate print size, required pixels, DPI/PPI, and uncompressed file size
Find Print Size
Find Required Pixels
Find DPI/PPI
in
cm
in
cm
Common Presets
Print Size
6.40 × 3.60 in
16:9 2.1 MP
Uncompressed File Size (approx.)
5.93 MB
Resolution (MP)
-
Aspect Ratio
-
Pixel Count
-
Key Formulas
Print size = Pixels ÷ DPI
Required pixels = Print size (in) × DPI
DPI = Pixels ÷ Print size (in)
Megapixels = (width × height) / 1,000,000
Uncompressed file size (bytes) = width × height × bitDepth / 8
1 inch = 2.54 cm
People Also Ask
🖨️ What DPI should I use for printing?
300 DPI is standard for high‑quality prints. 150 DPI may be acceptable for larger formats viewed from a distance.
📐 How do I calculate the maximum print size from an image?
Divide pixel dimensions by desired DPI. e.g., 1920 px / 300 DPI = 6.4 inches.
📏 What is the difference between DPI and PPI?
DPI (dots per inch) refers to printer resolution, PPI (pixels per inch) to screen/image resolution. Often used interchangeably.
📊 How is file size related to resolution?
Uncompressed file size = width × height × bit depth / 8 (bytes). Compression (JPEG) can reduce it significantly.
Understanding Image Resolution
Image resolution describes the detail an image holds. It can be expressed as pixel dimensions (width × height), as a pixel density (DPI/PPI), or as a physical print size. This calculator helps you convert between these values.
Why It Matters
- Printing: Ensure enough pixels for sharp prints at your desired size.
- Web/Screens: Optimize file size while maintaining visual quality.
- Storage: Estimate disk space required for raw images.
Aspect ratio (e.g., 16:9) describes the proportional relationship between width and height. It's preserved when scaling images for different uses.
Common Image Resolutions
| Name | Pixels (W×H) | Aspect | Megapixels |
|---|---|---|---|
| SD (480p) | 720×480 | 3:2 | 0.3 |
| HD (720p) | 1280×720 | 16:9 | 0.9 |
| Full HD (1080p) | 1920×1080 | 16:9 | 2.1 |
| 4K UHD | 3840×2160 | 16:9 | 8.3 |
| 5K | 5120×2880 | 16:9 | 14.7 |
| 8K | 7680×4320 | 16:9 | 33.2 |
| 12 MP photo | 4000×3000 | 4:3 | 12.0 |
Frequently Asked Questions
What is the difference between resolution and aspect ratio?
Resolution is the total number of pixels (width × height). Aspect ratio is the ratio of width to height (e.g., 16:9). Two images can have the same aspect ratio but different resolutions.
How many megapixels do I need for a large print?
A 300 DPI print requires about 2 megapixels for a 4×6", 8 MP for 8×10", and 24 MP for 16×20". Larger prints are often viewed from farther away, so lower DPI may be acceptable.
Can I increase resolution without losing quality?
Upscaling (adding pixels) can't create new detail – it just makes the image larger but softer. AI‑based upscaling can help, but original capture resolution is best.