Resolution & Megapixel Calculator
Enter a width and height to see the total pixels, the megapixels and the standard name (such as Full HD or 4K). You can also estimate a width × height from a number of megapixels.
How it is calculated
- Total pixels = width × height.
- Megapixels (MP) = total pixels ÷ 1,000,000 (1 MP = one million pixels, shown to 3 decimal places).
- Width × height from megapixels: the total pixels are megapixels × 1,000,000, and the tool finds whole-number dimensions that fit the aspect ratio (width : height). Width = √(pixels × width ratio ÷ height ratio) and height = width × height ratio ÷ width ratio. Because the sizes are rounded to whole numbers, the result does not match the megapixels you entered exactly; the difference is shown as a percentage.
Standard names
A standard name is shown only when the width × height matches the resolution exactly. Otherwise no name is shown.
| Name | Pixels (width × height) | Defined by |
|---|---|---|
| HD (720p) | 1,280 × 720 | SMPTE ST 296 |
| Full HD (1080p) | 1,920 × 1,080 | ITU-R BT.709 (HDTV) |
| UHD 4K | 3,840 × 2,160 | ITU-R BT.2020 (UHDTV) |
| UHD 8K | 7,680 × 4,320 | ITU-R BT.2020 (UHDTV) |
| DCI 2K | 2,048 × 1,080 | Digital Cinema Initiatives (DCI) system specification |
| DCI 4K | 4,096 × 2,160 | Digital Cinema Initiatives (DCI) system specification |
- The pixel sizes of these standards were checked against the standards documents when the Japanese version of this tool was made (October 2026). They were not checked again for this page.
- "Full HD", "UHD 4K" and "UHD 8K" are common names for these pixel sizes (the documents themselves call them HDTV and UHDTV).
- Names whose definitions could not be confirmed (such as SD at 720 × 480 or 720 × 576, QHD and WQHD) are not listed. A resolution with no name shown is not necessarily non-standard.
- There are two "4K" sizes: 3,840 × 2,160 (UHD, common on TVs and PCs) and 4,096 × 2,160 (DCI, the cinema size).
Examples
- 1,920 × 1,080: 2,073,600 pixels (about 2.074 MP), aspect ratio 16:9, Full HD.
- 4,000 × 3,000: 12,000,000 pixels (12 MP), aspect ratio 4:3, no standard name.
- 12 MP at 4:3: 4,000 × 3,000.
- 8 MP at 16:9: 3,771 × 2,121 (7,998,291 pixels, about −0.02% from the 8 MP you entered).
Notes
- Width and height must be whole numbers from 1 to 999,999. Megapixels must be a number greater than 0 with up to 6 decimal places. Use a period as the decimal separator; commas are accepted only as thousands separators.
- A camera's "megapixels" can mean the total pixels of the sensor or the pixels of the recorded image, depending on the model. This tool simply multiplies the width by the height you enter.
- The aspect ratio is shown as an exact reduced ratio, and when it is within 1% of a common ratio the tool adds "about 16:9" and so on (the same rule as the Aspect Ratio Calculator).
- To find the new size when resizing an image, see the Image Resize Calculator.
Frequently asked questions
How many pixels is Full HD?
1,920 × 1,080, which is 2,073,600 pixels (about 2.07 megapixels).
How many pixels is 4K?
UHD 4K, used on TVs, is 3,840 × 2,160 (about 8.3 megapixels). DCI 4K, used in cinemas, is 4,096 × 2,160 (about 8.8 megapixels).
What is a megapixel?
A way of counting pixels in units of one million. 12 megapixels is 12 million pixels.