4:5 Portrait Calculator
4:5 portrait — Instagram’s tallest feed frame and the classic poster shape. Get the exact partner dimension.
4:5 (0.8:1) portrait maximizes vertical space in the Instagram feed — 1080×1350 fills the screen taller than a square without getting cropped the way 9:16 does in feed. Posters at 8×10, 16×20 and 24×30 are the same ratio family. Solve from width or height and export without surprise crops.
1920 × 2400
Exact ratio: 4:5 · CSS: aspect-ratio: 4 / 5 · padding-top fallback: 125.00%
Formula
height = width × 5 ÷ 4
width = height × 4 ÷ 5
// padding-top fallback: 125.00% — keeps layout stable before the image loads
aspect-ratio: 4 / 5 — modern replacement for the padding hack
All math runs locally in your browser. No upload. Type either side, the other solves live — and the URL updates so you can share an exact pair (?w=1920&rw=4&rh=5) or bookmark a preset.
Common 4:5 resolutions
| Width | Height | Use |
|---|---|---|
| 320px | 400px | |
| 640px | 800px | |
| 1280px | 1600px | |
| 1920px | 2400px | |
| 2560px | 3200px | |
| 3840px | 4800px | 4K |
| 5120px | 6400px | |
| 7680px | 9600px |
Exact known sizes in this ratio
- 1080×1350 — 1080×1350 Portrait 4:5 (Instagram portrait feed)
When to use 4:5
- Instagram portrait feed post (1080×1350)
- Poster prints 8×10, 16×20
- Pinterest pins (close to 4:5, feeds prefer tall)
Pitfalls to avoid
- Instagram feed caps at 4:5 — taller than that gets cropped top/bottom to 4:5
- Mixing 4:5 and 9:16 masters — pick one tall ratio and commit
CSS snippet
Modern:
.frame { aspect-ratio: 4 / 5; width: 100%; overflow: hidden; }
.frame > img { width: 100%; height: 100%; object-fit: cover; }Legacy padding hack (for very old browsers):
.wrap { position: relative; width: 100%; padding-top: 125.00%; }
.wrap > * { position: absolute; inset: 0; }Pair with object-fit: contain to letterbox without cropping, or cover to fill and crop safely.
Platform reference
Frequently asked
What is the 4:5 size for Instagram?
1080×1350 (or half: 540×675). It is the tallest image Instagram shows uncropped in feed.
Is 4:5 the same as 5:4?
No — 4:5 is portrait (taller than wide); 5:4 is landscape. They are reciprocals.
How is 4:5 different from 9:16?
4:5 is modestly portrait; 9:16 is aggressively vertical (almost 2× tall). Feed uses 4:5, Stories/Reels use 9:16.
Tip: add ?w=1920 or ?h=1080 to this URL to prefill the calculator — useful for linking from a spec doc.
Other ratios
- 16:9 Aspect Ratio Calculator
- 4:3 Aspect Ratio Calculator
- 1:1 Square Calculator
- 9:16 Vertical Calculator
- 21:9 Ultrawide Calculator
- 3:2 Aspect Ratio Calculator
- 16:10 Aspect Ratio Calculator
- 2:1 Aspect Ratio Calculator
Look up by resolution
- 1920×1080 — 1920×1080 Full HD
- 1280×720 — 1280×720 HD
- 3840×2160 — 3840×2160 4K UHD
- 2560×1440 — 2560×1440 QHD
- 1366×768 — 1366×768 WXGA
- 3440×1440 — 3440×1440 UW-QHD
What aspect ratio is 1920×1080? → · Full FAQ →