3840 × 2160 resolution
3840 × 2160 has a 16:9 aspect ratio and contains 8,294,400 pixels (8.29 MP). The exact 16:9 Ultra HD resolution used by consumer 4K displays and video.
Quick answer
What aspect ratio is 3840 × 2160?
3840 × 2160 reduces exactly to 16:9, the same shape as 16:9. No approximation is needed.
gcd(3840, 2160) = 2403840 ÷ 240 : 2160 ÷ 240 = 16:9Treat 3840 × 2160 as a landscape video frame. Keep both dimensions linked when resizing. Changing only one edge changes the ratio and can stretch the image; cropping or adding canvas space is safer when the destination uses another shape.
Pixel count and memory
The frame contains 8,294,400 pixels, or 8.29 megapixels. Uncompressed pixel memory is about 23.73 MiB for RGB or 31.64 MiB for RGBA.
Those are working-memory estimates, not JPG, PNG or video file sizes. Compression, bit depth, frame rate and codec change the stored file size. For video, use the bitrate-based file size calculator.
How to use this size
Use it as a video frame only after confirming the delivery specification, frame rate and codec. The dimensions are encoder-friendly because both axes are even, but bitrate still determines compressed file size.
Before export, confirm whether the destination requests this exact resolution, only the 16:9 ratio, or a maximum file size. These are different requirements. Use the image checker to verify an existing file without uploading it.
Scale 3840 × 2160 proportionally
These sizes keep the same shape. Whole-number results are exact; fractional results are rounded to the nearest pixel and may differ by a tiny amount.
| Scale | Dimensions | Pixel note |
|---|---|---|
| 25% | 960 × 540 | Exact integer scale |
| 50% | 1,920 × 1,080 | Exact integer scale |
| 75% | 2,880 × 1,620 | Exact integer scale |
| 100% | 3,840 × 2,160 | Exact integer scale |
| 125% | 4,800 × 2,700 | Exact integer scale |
| 150% | 5,760 × 3,240 | Exact integer scale |
| 200% | 7,680 × 4,320 | Exact integer scale |
Print size at common PPI values
PPI converts pixels to physical dimensions; it does not change the aspect ratio. Print size equals pixels divided by PPI.
| Resolution density | Size in inches | Size in millimetres |
|---|---|---|
| 72 PPI | 53.33 × 30 in | 1,354.67 × 762 mm |
| 96 PPI | 40 × 22.5 in | 1,016 × 571.5 mm |
| 150 PPI | 25.6 × 14.4 in | 650.24 × 365.76 mm |
| 300 PPI | 12.8 × 7.2 in | 325.12 × 182.88 mm |
Printer capability, viewing distance, paper and sharpening also affect perceived quality. Plan another density with the print size and DPI calculator.
Crop or fit 3840 × 2160 into another ratio
Crop size is the largest centered rectangle of the target shape that fits inside the source. Fit canvas keeps every source pixel and adds space around it. Crop-loss values use rounded whole-pixel dimensions.
| Target | Largest crop | Area lost | Smallest fit canvas |
|---|---|---|---|
| 1:1 | 2,160 × 2,160 | 43.75% | 3,840 × 3,840 |
| 4:5 | 1,728 × 2,160 | 55% | 3,840 × 4,800 |
| 16:9 | 3,840 × 2,160 | 0% | 3,840 × 2,160 |
| 9:16 | 1,215 × 2,160 | 68.36% | 3,840 × 6,827 |
Subject placement can make a mathematically centered crop unsuitable. Preview the edges with the crop loss calculator, or calculate padding and an FFmpeg command with the letterbox calculator.
Resolution, ratio and display size are different
Resolution is 3840 pixels wide by 2160 pixels high. Aspect ratio is the reduced shape 16:9. Display or print size requires a physical measurement or pixel density. Two files can share 16:9 while having very different pixel counts.
For example, scaling this frame to 50% produces 1,920 × 1,080. It keeps the shape but contains one quarter of the original pixels because both axes are halved.
Frequently asked questions
Is 3840 × 2160 16:9?
Yes. It reduces exactly to 16:9.
How many megapixels is 3840 × 2160?
It contains 8,294,400 pixels, which is 8.29 megapixels using one million pixels per megapixel.
What is half of 3840 × 2160?
At 50% on both axes, the size is 1,920 × 1,080. Both dimensions remain whole pixels.
Can I change it to 16:9 without stretching?
It is already exactly 16:9, so proportional resizing will not stretch it.
Related resolution guides
Compare resolutions with the same ratio first, then nearby sizes used in a similar workflow.