4:5 Aspect Ratio Calculator
4:5 is the Instagram portrait ratio. It takes up more feed real-estate than a square and stops the scroll. Use this calculator to size any image to 4:5.
Why 4:5 dominates the Instagram feed
4:5 is the tallest ratio Instagram allows in feed posts. At 1080×1350 pixels, it occupies 25% more vertical space than a 1:1 square. More feed space means more time on screen, which means more chance a viewer reads the caption and engages.
Most growth-focused creators and brands have moved to 4:5 by default for any feed image meant to drive engagement. Square is still fine for designs that need to be symmetric or used elsewhere, but 4:5 is the new default for anything Instagram-native.
Common 4:5 dimensions
1080×1350 is the standard 4:5 size for Instagram. If you're working at higher resolution, 2160×2700 or 4320×5400 are also 4:5 and Instagram will downscale cleanly. Avoid uploading anything narrower than 1080. Instagram will upscale and the result looks soft.
What gets cropped if you ignore 4:5
Upload a 16:9 horizontal image and Instagram crops the top and bottom to fit a 1.91:1 letterbox in the feed. Upload a 9:16 vertical and Instagram crops the top and bottom heavily to fit 4:5. The takeaway: shoot for 4:5 from the start, or use the calculator's image mode to crop with intention before upload.
How the calculator works
Math, resizing, and image cropping in one place. Free, no signup, no watermark.
Enter your dimensions
Type any width and height in pixels. We simplify the ratio with the greatest common divisor and tell you the closest standard match.
Resize without losing proportions
Switch to Resize. Keep the original ratio while scaling to a new width or height. Round to whole pixels with one click.
Or drop in an image
Image mode shows a smart-cropped preview for every social platform: Instagram, TikTok, YouTube, LinkedIn, Pinterest, and more.
Download the right size
Grab a single PNG at the exact dimensions you need, or download every social platform size at once as a ZIP.
Built for the work you actually do
Every social platform. Every common ratio. Image-aware so you see what gets cropped before you post.
Sizing for Instagram
Square, portrait, story, Reel. Instagram has four valid sizes and the wrong one gets your post cropped. Pick the platform, get the pixels.
YouTube videos and thumbnails
Videos at 1920×1080 or 3840×2160. Thumbnails at 1280×720. Shorts at 1080×1920. Get the right size without searching the YouTube docs.
TikTok and Reels covers
9:16 vertical at 1080×1920. Drop your cover art, download a perfectly cropped version that won't get squashed.
DSLR and stock photos
Original 3:2 photo, target 4:5 Instagram portrait? Resize without distortion. Center crop preview shows what gets cut.
Designing for screens
Build mockups that fit 16:9 monitors, 9:16 phones, or 21:9 ultrawides. Get pixel dimensions before you open Figma.
Bulk export for a campaign
One image, every social platform size. Drop it in image mode, hit download all. ZIP file with PNGs ready to post.
Social media aspect ratios in 2026
Every common social platform format with the recommended pixel size and ratio.
| Platform | Format | Pixels | Ratio |
|---|---|---|---|
| Square post | 1080 × 1080 | 1:1 | |
| Portrait post | 1080 × 1350 | 4:5 | |
| Landscape post | 1080 × 566 | 191:100 | |
| Story | 1080 × 1920 | 9:16 | |
| Reel | 1080 × 1920 | 9:16 | |
| TikTok | Video | 1080 × 1920 | 9:16 |
| YouTube | Video | 1920 × 1080 | 16:9 |
| YouTube | Shorts | 1080 × 1920 | 9:16 |
| YouTube | Thumbnail | 1280 × 720 | 16:9 |
| Feed post | 1200 × 630 | 191:100 | |
| Story | 1080 × 1920 | 9:16 | |
| Cover | 851 × 315 | 851:315 | |
| Square post | 1200 × 1200 | 1:1 | |
| Cover | 1584 × 396 | 4:1 | |
| X (Twitter) | Image post | 1600 × 900 | 16:9 |
| X (Twitter) | Header | 1500 × 500 | 3:1 |
| Standard pin | 1000 × 1500 | 2:3 | |
| Tall pin | 1000 × 2100 | 10:21 | |
| Snapchat | Snap / Story | 1080 × 1920 | 9:16 |
Last verified May 2026.
Other ratios
Pre-filled calculators for the most common ratios.
Frequently asked questions
Why is 1080×1350 the recommended Instagram portrait size?
It's exactly 4:5 ratio at 1080 wide (Instagram's native display width). Anything narrower gets upscaled and softens; anything wider gets resampled and may shift colors slightly.
Can I use 4:5 for LinkedIn or Twitter too?
LinkedIn supports 4:5 in feed posts. Twitter / X displays 4:5 with letterboxing in feed but expands fully when clicked. For multi-platform, 4:5 is a defensible default if Instagram is primary.
Is 4:5 the same as 8:10?
Yes. 8÷10 = 4÷5 = 0.8. Different way of writing the same ratio.
What is an aspect ratio?
Aspect ratio is the relationship between width and height, written as width:height. A 1920×1080 image has a 16:9 aspect ratio because 1920÷120 = 16 and 1080÷120 = 9. The ratio describes the shape of the rectangle, independent of size. A 1280×720 image is also 16:9.
How do I calculate the aspect ratio of an image?
Divide width by height to get the decimal ratio. To get the simplified form, find the greatest common divisor (GCD) of width and height and divide both by it. 1920÷1080 = 1.778, GCD(1920, 1080) = 120, so the ratio is 16:9. The calculator above does this instantly.
Is 1920×1080 a 16:9 aspect ratio?
Yes. 1920÷1080 = 1.778, which equals 16÷9. Full HD video, most monitors, and standard YouTube videos are all 16:9 at 1920×1080.
What aspect ratio is best for Instagram?
Instagram supports four ratios. Square 1:1 at 1080×1080 for feed posts. Portrait 4:5 at 1080×1350 for taller feed posts (recommended for organic reach). Landscape 1.91:1 at 1080×566 for wide posts. Vertical 9:16 at 1080×1920 for Stories and Reels.
What ratio should I use for TikTok?
TikTok uses 9:16 vertical at 1080×1920 pixels. The same applies to Instagram Reels and YouTube Shorts. One vertical export covers all three.
More free tools you'll like
Built by Krumzi. Same no-signup, no-watermark deal.
Color Picker From Image
Pull HEX, RGB, HSL, HSB, OKLCH, and CMYK out of any image. Auto-extracts the dominant palette.
Mesh Gradient Generator
Build vibrant gradient backgrounds. Pick colors, reshuffle, export PNG.
Animated Background Generator
Looping gradient video backgrounds for slides, intros, and reels.
Animated Counter
Slick number animations for milestones and stats. Export MP4.
Screenshot to Video
Wrap product screenshots in animated gradients. Perfect for launches.
This Free Tool Is Just the Start
Krumzi designs complete social media graphics and videos from a text description. No templates. No design skills. Just describe what you want and watch AI build it.
Every layout decision. Every color choice. Every font and composition. Done in seconds. Fully editable. Fully yours.
No credit card required