Smallest whole-pixel size 4 × 5.
In CSS: aspect-ratio: 4 / 5. Rotated it becomes 5:4.
Where 4:5 is used
Instagram portrait posts, Facebook feed images.
The tallest ratio Instagram shows uncropped in the feed, which makes it the highest-real-estate option for organic reach.
Rendered live with aspect-ratio: 4 / 5.
4:5 resolutions
Every size below is exactly 4:5 — no rounding. Sizes marked as a standard are named display resolutions.
| Resolution | Width | Height | Megapixels | Standard |
|---|---|---|---|---|
| 160 × 200 | 160 | 200 | 0.03 | — |
| 164 × 205 | 164 | 205 | 0.03 | — |
| 168 × 210 | 168 | 210 | 0.04 | — |
| 172 × 215 | 172 | 215 | 0.04 | — |
| 176 × 220 | 176 | 220 | 0.04 | — |
| 180 × 225 | 180 | 225 | 0.04 | — |
| 184 × 230 | 184 | 230 | 0.04 | — |
| 188 × 235 | 188 | 235 | 0.04 | — |
| 192 × 240 | 192 | 240 | 0.05 | — |
| 196 × 245 | 196 | 245 | 0.05 | — |
| 200 × 250 | 200 | 250 | 0.05 | — |
| 204 × 255 | 204 | 255 | 0.05 | — |
| 208 × 260 | 208 | 260 | 0.05 | — |
| 212 × 265 | 212 | 265 | 0.06 | — |
| 216 × 270 | 216 | 270 | 0.06 | — |
| 220 × 275 | 220 | 275 | 0.06 | — |
| 224 × 280 | 224 | 280 | 0.06 | — |
| 228 × 285 | 228 | 285 | 0.06 | — |
| 232 × 290 | 232 | 290 | 0.07 | — |
| 236 × 295 | 236 | 295 | 0.07 | — |
| 240 × 300 | 240 | 300 | 0.07 | — |
| 320 × 400 | 320 | 400 | 0.13 | — |
| 480 × 600 | 480 | 600 | 0.29 | — |
| 640 × 800 | 640 | 800 | 0.51 | — |
| 720 × 900 | 720 | 900 | 0.65 | — |
| 800 × 1000 | 800 | 1000 | 0.8 | — |
| 960 × 1200 | 960 | 1200 | 1.15 | — |
| 1080 × 1350 | 1080 | 1350 | 1.46 | — |
| 1200 × 1500 | 1200 | 1500 | 1.8 | — |
| 1280 × 1600 | 1280 | 1600 | 2.05 | — |
| 1440 × 1800 | 1440 | 1800 | 2.59 | — |
| 1600 × 2000 | 1600 | 2000 | 3.2 | — |
| 1920 × 2400 | 1920 | 2400 | 4.61 | — |
| 2048 × 2560 | 2048 | 2560 | 5.24 | — |
| 2560 × 3200 | 2560 | 3200 | 8.19 | — |
| 3200 × 4000 | 3200 | 4000 | 12.8 | — |
| 3840 × 4800 | 3840 | 4800 | 18.43 | — |
| 5120 × 6400 | 5120 | 6400 | 32.77 | — |
| 7680 × 9600 | 7680 | 9600 | 73.73 | — |
Using 4:5 in CSS
/* Modern — one line */
.box { aspect-ratio: 4 / 5; }
/* With a fixed width */
.box { width: 100%; max-width: 800px; aspect-ratio: 4 / 5; }
/* Legacy padding-top hack, if you still need it */
.box-legacy { position: relative; }
.box-legacy::before { content: ""; display: block; padding-top: 125%; }
.box-legacy > * { position: absolute; inset: 0; }Questions about 4:5
What resolution is 4:5?
4:5 is a ratio, not a fixed resolution — any size where width ÷ height equals 0.8 qualifies. The smallest whole-pixel pair is 4 × 5, and common ones include 640 × 800, 720 × 900, 800 × 1000, 960 × 1200.
What is 4:5 used for?
Instagram portrait posts, Facebook feed images.
How do I set 4:5 in CSS?
Use the aspect-ratio property: aspect-ratio: 4 / 5;. The element then keeps that shape at any width. It is supported in every current browser.
What is 4:5 the other way round?
Rotated to landscape it becomes 5:4 — the same shape, turned 90 degrees.
How do I calculate a 4:5 height from a width?
Multiply the width by 1.25. For example 1080 × 1.25 = 1350. The calculator does it both directions.