Instagram Post Size Checker — Dimensions & Aspect Ratios
Instagram supports multiple aspect ratios for feed posts, but using the wrong size means auto-cropping, blurry images, or wasted screen space. A portrait photo that's too tall gets its top and bottom cut off. A landscape photo that's too wide loses the sides. A square image that's only 600 pixels wide looks soft and pixelated on modern phones.
This guide covers the correct Instagram post sizes for every format, how aspect ratios work, why dimensions matter for quality and engagement, and the most common sizing problems creators run into.
Instagram Post Specs
Best Size: 1080×1350 px (4:5)
Square: 1080×1080 px (1:1)
Landscape: 1080×566 px (1.91:1)
Min Width: 320 px (1080 recommended)
Max Ratio: 1.91:1 to 4:5
Format: JPG or PNG
Max File Size: 30 MB
Max Carousel: 20 slides
Recommended Instagram Post Sizes
Instagram supports three main orientations for feed posts. The best choice depends on your content and engagement goals.
| Format | Size (px) | Aspect Ratio | Feed Presence | Best For |
|---|
| Portrait | 1080×1350 | 4:5 | Largest — fills ~20% more screen than square | Maximum engagement, product shots, faces |
| Square | 1080×1080 | 1:1 | Standard — classic Instagram format | Grid consistency, product flatlays, graphics |
| Landscape | 1080×566 | 1.91:1 | Smallest — thin horizontal strip | Panoramas, wide shots, cinematic content |
| Carousel | 1080×1350 or 1080×1080 | 4:5 or 1:1 | All slides must match | Tutorials, product series, storytelling |
Why 4:5 portrait wins: at 1080×1350, your post takes up the maximum allowed vertical space in the feed. That means more screen real estate, longer scroll-stop time, and higher engagement compared to square or landscape. Most top-performing Instagram accounts use 4:5 as their default.
Instagram Aspect Ratios Explained
Instagram accepts aspect ratios from 1.91:1 (widest landscape) to 4:5 (tallest portrait). Anything outside this range gets auto-cropped to fit.
| Ratio | Dimensions | What Happens |
|---|
| 4:5 (portrait) | 1080×1350 | Fills maximum feed height — best for engagement |
| 1:1 (square) | 1080×1080 | Standard display, no cropping |
| 1.91:1 (landscape) | 1080×566 | Thin strip, significant white space above/below |
| Taller than 4:5 (e.g. 9:16) | 1080×1920 | Auto-cropped to 4:5 — top and bottom cut off |
| Wider than 1.91:1 | e.g. 2560×1080 | Auto-cropped to 1.91:1 — sides cut off |
Carousel aspect ratio rules
- All slides must use the same aspect ratio — Instagram forces all carousel slides to match the first slide's ratio.
- If you upload a mix of portrait and landscape images, Instagram crops every slide to match the first one.
- Use 4:5 or 1:1 for every slide to avoid unexpected cropping.
Profile grid display
Regardless of your post's aspect ratio, the profile grid always displays posts as 1:1 squares. Portrait posts are center-cropped vertically, landscape posts are center-cropped horizontally. If your grid aesthetic matters, design with the center square crop in mind.
Why Instagram Post Size Matters
- Feed real estate drives engagement — a 4:5 portrait post fills ~20% more screen than a 1:1 square and ~60% more than a 1.91:1 landscape. More screen space means more attention time and higher engagement.
- Instagram compresses every upload — all images are re-encoded on upload. If your source file is low resolution or already compressed, the additional compression causes visible blur. Starting at 1080 px wide gives Instagram the most data to work with.
- Wrong ratios get auto-cropped — images taller than 4:5 or wider than 1.91:1 are silently cropped. There's no warning and no undo. Your carefully composed image loses its edges without your control.
- Profile grid crops to 1:1 — even if you post 4:5, the grid shows a square center-crop. Faces, text, or key details near the top or bottom of a portrait post may be hidden on your profile grid.
- Carousel consistency — mismatched aspect ratios in carousels cause unpredictable cropping. Every slide must match or the results look broken.
Common Instagram Post Size Problems
Photo is auto-cropped on upload
Your image is outside Instagram's 1.91:1 to 4:5 aspect ratio range. A 9:16 story-sized image (1080×1920) will be cropped to 4:5 (1080×1350), cutting 570 px from the combined top and bottom. Pre-crop to a supported ratio before uploading.
Image looks blurry in the feed
Your source image is under 1080 px wide or already heavily compressed. Instagram re-encodes everything, so low-quality sources get visibly blurry. Upload at 1080 px wide minimum with JPG at 90%+ quality or PNG for graphics.
Post looks tiny in the feed
You're using a landscape ratio (1.91:1). Landscape posts display as a thin horizontal strip with significant space above and below. Switch to 4:5 portrait for maximum feed presence, or 1:1 square for a balanced look.
Face or text cut off in the profile grid
The profile grid crops all posts to 1:1 squares from the center. A face at the top of a 4:5 portrait or text at the bottom gets hidden in the grid view. Center key elements vertically so they survive the square crop.
Carousel slides cropped inconsistently
Instagram forces all carousel slides to match the first slide's aspect ratio. If your first slide is 1:1 and the second is 4:5, the second gets cropped to 1:1. Use the same ratio for every slide.
Image colors look different after uploading
Instagram converts all images to sRGB color space. Images in Adobe RGB, ProPhoto RGB, or CMYK may shift colors on upload. Export in sRGB before uploading to avoid surprises.
Instagram Post Size Best Practices
- Use 4:5 portrait (1080×1350) as your default — maximum feed presence, maximum engagement. Only use square or landscape when the content specifically calls for it.
- Always upload at 1080 px wide — this is the width Instagram displays at on most phones. Smaller widths get upscaled and look blurry. Larger widths are downscaled (no benefit, wasted file size).
- Use JPG for photos, PNG for graphics — JPG at 90%+ quality gives the best file-size-to-quality ratio for photographs. PNG preserves sharp edges for text overlays, logos, and illustrations.
- Export in sRGB color space — Instagram converts to sRGB on upload. Other color spaces may shift. Export in sRGB to see what you get.
- Center key content for the grid crop — the profile grid crops to 1:1 from center. Faces, text, and important details should be in the center of the image, not near edges.
- Use the same ratio for all carousel slides — mismatched ratios cause Instagram to force-crop every slide to match the first one. Decide on 4:5 or 1:1 and apply it to all slides.
- Don't add black bars to force a ratio — adding letterbox bars inside the image wastes pixels and makes the post look smaller in the feed. Crop the actual content to fit instead.
- Preview Stories and Reels separately — feed posts use different ratios than Stories (9:16) and Reels (9:16). Don't reuse a feed image for Stories without re-sizing. Check with the Instagram Story safe zone tool.
Check your Instagram content before posting:
Instagram Post Size FAQ
What size should an Instagram post be?▼
1080×1350 pixels (4:5 portrait) for maximum feed presence. Also supported: 1080×1080 (square) and 1080×566 (landscape). Always upload at 1080 px wide minimum.
What aspect ratios does Instagram support for posts?▼
Instagram supports ratios from 1.91:1 (landscape) to 4:5 (portrait). Common choices: 1:1 square, 4:5 portrait, 1.91:1 landscape. Ratios outside this range are auto-cropped.
Why does Instagram crop my photo?▼
Your image's aspect ratio is outside the 1.91:1 to 4:5 range. Images taller than 4:5 get top/bottom cropped. Images wider than 1.91:1 get side-cropped. Pre-crop to a supported ratio before uploading.
What is the best Instagram post size for engagement?▼
4:5 portrait (1080×1350) takes up the most screen space in the feed — about 20% more than square and 60% more than landscape. More screen space means more attention and higher engagement.
Why does my Instagram photo look blurry?▼
Instagram compresses all uploads. Source images under 1080 px wide or already compressed become visibly blurry. Upload at 1080 px wide minimum. Use JPG at 90%+ quality for photos, PNG for graphics with text.