Posting to Instagram takes under two minutes once you know the steps. This guide covers single photos, carousels, image specs, and captions that actually get read.
> Quick answer: Tap + in the Instagram app, select your image or carousel slides, edit, write your caption, add hashtags and tags, and tap Share.
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How to Post a Single Photo to Instagram Feed
Single photo posts are the fastest way to get something live on your feed.
Open Instagram and tap the + icon
Open the Instagram app on your phone. Tap the + icon at the bottom of the screen. Select Post from the menu that appears.
Select a photo from your library or take a new one
Your camera roll opens automatically. Tap any photo to select it. Or tap the camera icon to shoot a new one on the spot.
Edit, filter, and crop your image
Instagram's built-in editor lets you crop, filter, adjust brightness, sharpen, and add text overlays. Apply your edits, then tap Next to continue.
Add caption, hashtags, and location tags
Write your caption in the text field. Captions can be up to 2,200 characters. Add hashtags, then tap Tag People or Add Location for extra discoverability. Tap Next.
Tap Share to publish
Review your settings one more time. Tap Share. Your post is live immediately.
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How to Post a Carousel (Multiple Photos or Videos)
Carousels let you tell a longer story in one swipeable post.
Tap + and select carousel format
Tap + at the bottom of the screen. Select Post, then tap the multiple-select icon (two overlapping squares) in the lower-right corner of the photo picker.
Upload up to 20 photos and/or videos
Per Instagram's Help Center, carousels support up to 20 photos and videos in a single post. Select your items in the order you want them displayed, then tap Next.
Edit each item individually
Tap each slide to apply its own filter or adjustments. You can add music to photo-only carousels before sharing. Music is not available on carousels that contain video.
Add captions and tags
Write one caption that covers the full carousel. Tag people, brands, and locations exactly as you would for a single photo post.
Publish to feed
Tap Share. All slides go live together as one post.
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Image Specifications and Best Practices
Getting your specs right prevents cropped or blurry posts in feed.
Recommended dimensions: 1080 x 1350 pixels (4:5 portrait)
Portrait at 1080 x 1350 px fills the most vertical screen space in feed. More screen space means more attention before someone scrolls past. Square (1080 x 1080 px) and landscape (1080 x 566 px) are also supported.
File formats: JPG or PNG, up to 8MB
Instagram accepts JPG and PNG files up to 8MB. If your image exceeds 1080px wide, Instagram scales it down automatically. Images under 320px wide get scaled up.
Aspect ratio ranges: 1.91:1 to 4:5 for feed
Instagram accepts aspect ratios between 1.91:1 (landscape) and 4:5 (portrait) for feed posts. Images outside that range get cropped automatically. All posts appear in vertical format on your profile grid, regardless of original ratio.
Why vertical images drive more engagement
Portrait images fill more of a phone screen on mobile. More visible area means longer viewing time. Crop or shoot to 4:5 whenever you can.
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Write Captions and Tags That Drive Engagement
A strong caption turns a viewer into a follower. A weak one gets scrolled past.
Hook readers in the first 125 characters
Only the first ~125 characters appear in feed before the "more" tap. Lead with your sharpest line. Ask a question. Make a bold claim. Give a tip worth reading.
Use 3-5 relevant hashtags strategically
Three to five targeted hashtags outperform a wall of 30 generic ones. Pick hashtags your audience actually follows. Place them at the end of your caption or drop them in the first comment.
Tag people, brands, and locations
Tagging expands who sees your post. Tag collaborators, the brands you mention, and the location where a photo was taken. Each tag is a new discovery path.
Keep captions concise for best results
Short captions get read. Long ones get skipped. If you have more to say, put the hook first and expand below the fold.
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Frequently Asked Questions
How do I post to Instagram from my phone?
Open the Instagram app, tap the + icon at the bottom of the screen, select Post, choose a photo from your library or take a new one, edit it, write a caption with hashtags, and tap Share.
What image size is best for an Instagram feed post?
1080 x 1350 pixels (4:5 portrait ratio) is recommended. It fills the most screen space in feed and performs well on most phones. Instagram also supports square (1080 x 1080 px) and landscape (1080 x 566 px) formats.