Resolution calculator
Full Screen Wallpaper Size for Mobile
A full-screen wallpaper has two requirements: enough pixels for the display and the same shape as the screen. Pixel count controls detail; aspect ratio controls crop.
Separate resolution from aspect ratio
Resolution is the pixel grid, such as 1080 × 2400. Aspect ratio is the shape, such as 20:9. Two screens can share a ratio and use different pixel counts.
A 720 × 1600 file and a 1080 × 2400 file both use 20:9. Both fit the same shape, but the second contains more pixels and can show more detail.
Useful portrait references
| Screen | Portrait pixels | Approximate shape |
|---|---|---|
| iPhone 16 Pro | 1206 × 2622 | 19.6:9 |
| iPhone 16 Pro Max | 1320 × 2868 | 19.6:9 |
| Pixel 9 | 1080 × 2424 | 20.2:9 |
| Pixel 9 Pro XL | 1344 × 2992 | ≈ 20:9 |
| Galaxy S25 Ultra | 1440 × 3120 | 19.5:9 |
| Generic modern Android | 1080 × 2400 | 20:9 |
| Classic Full HD portrait | 1080 × 1920 | 16:9 |
Calculate a size from a ratio
When you know the ratio and choose a width, calculate height with:
Height formula: height = width × ratio height ÷ ratio width
- 20:9 at 1080 wide →
1080 × 20 ÷ 9 = 2400 - 16:9 at 1080 wide →
1080 × 16 ÷ 9 = 1920 - 19.5:9 at 1440 wide →
1440 × 19.5 ÷ 9 = 3120
Round the result to a whole pixel. If you know the exact phone, use the manufacturer or screenshot resolution instead of a calculated approximation.
What “full screen” means for the source
A source photo fills the mobile canvas without crop only when its aspect ratio matches the target. Otherwise:
- Fill reaches every edge and removes overflow.
- Fit keeps every source pixel and adds space.
- Blur fill keeps the full source over an extended background.
Adding more output pixels does not change this geometry. Upscaling a 4:3 photo to a large 20:9 file still leaves a shape mismatch.
Reserve a full-screen safe area
Keep critical content inside roughly the central 80–86% of the frame. The exact UI changes across phones, but this buffer protects faces and text from rounded corners, camera cutouts, the lock-screen clock, widgets, and the bottom dock.
The screenshot test
Make a screenshot on the target phone and inspect its dimensions. Export the wallpaper at the same pixel grid, set it on the phone, and compare screenshots of the Lock and Home screens. That closed loop is more reliable than any universal size chart.
References
Primary and product sources accessed July 30, 2026: