How to Post Mixed Photos on Instagram

Posting different-sized photos together in one Instagram carousel is one of those things that seems like it should be simple, but ends up cropping your shots in weird, frustrating ways. The good news is that you can absolutely mix horizontal, vertical, and square images in a single post without losing the edges of your best photos. This guide will show you exactly how to do it using two simple, actionable methods and explain why it's such a great strategy for creating more dynamic, engaging content.

Why Mixed-Sized Photos Make Your Carousels More Engaging

Before getting into the how-to, it's worth understanding why this is a powerful creative technique. It's more than just a technical workaround, it’s a strategic choice that can dramatically improve your content.

• It Creates Visual Variety: An endless stream of perfectly square photos can get a little monotonous. By introducing a mix of vertical portraits and wide landscapes, you break up the predictability. This small change in rhythm keeps your audience curious and engaged, encouraging them to keep swiping to see what's next. It’s an easy way to make your feed feel more thoughtful and professionally curated.
• It Improves Your Storytelling: Different aspect ratios emphasize different things. A sprawling landscape shot (1.91:1) is perfect for establishing a scene or showing the scale of a location. A tall portrait photo (4:5) is great for focusing on a person or a detailed subject, as it fills up more of the mobile screen. By using both in one carousel, you can tell a more compelling story, starting wide to set the context and then punching in with a vertical shot for the key detail.
• It Displays Every Photo Properly: Sometimes a photo is just meant to be wide or tall. Instead of letting Instagram awkwardly crop your beautiful landscape photo into a square, this technique allows each image to be presented in its intended orientation. You no longer have to sacrifice composition just to fit everything into the same box.

The “One Little Thing” You Need to Know About Instagram Carousels

There’s one fundamental rule that governs all carousel posts, and understanding it is the key to mastering mixed-photo posts. Here it is:

Instagram sets the aspect ratio for the entire carousel based on the first photo you select.

That’s it. That’s the entire secret. When you start building your carousel, whatever shape your first image is dictates the frame for every other slide in that post. Let’s break that down:

• If your first photo is a square (1:1 aspect ratio), Instagram will force all subsequent photos, whether vertical or horizontal, into a square frame to match. This will crop your vertical and landscape shots.
• If your first photo is a portrait (up to 4:5 aspect ratio), all your other photos will be placed inside that same tall, rectangular frame. Your squares and landscapes will appear with letterboxing (borders).
• If your first photo is a landscape (up to 1.91:1), all your photos will be placed inside that wide frame. Your squares and portraits will have heavy pillarboxing (side borders).

Once you grasp this single concept, you stop fighting the app and start using this rule to your advantage. Now, let’s go through the methods to make it happen.

How to Post Mixed Vertical and Horizontal Photos: 2 Easy Methods

There are two main ways to tackle this. The first is a fast, in-app solution perfect for when you're on the go. The second offers complete creative control for a more polished, branded look.

Method 1: The "No Extra Apps Needed" In-App Fix

Use this method when you just need to get a post up quickly and aren't concerned with the exact color of the borders Instagram automatically adds. It's fast, simple, and works directly within the Instagram app.

Step-by-Step Instructions:

1. Start a New Post: Open Instagram and tap the "+" icon at the bottom, then choose "Post."
2. Select Multiple Photos: Before choosing any images, tap the "Select Multiple" icon (it looks like two overlapping squares) so you can build your carousel.
3. Choose Your FIRST Photo Strategically: This is the most important step. Find the photo you want to be your 'hero' image and the one that has the aspect ratio you want for the whole post. For maximum screen space, a vertical 4:5 image is almost always the best choice. Tap on that first.
4. Set the Frame Size: After selecting your first photo, look at its thumbnail in the bottom viewing panel. In the bottom-left corner of the thumbnail, you'll see a small 'expand' icon (two arrows pointing outwards). Tap it. This will snap the preview for that photo out of the default square into its filled-out aspect ratio (e.g., from 1:1 to 4:5). You have now locked in the frame for the entire carousel.
5. Select the Rest of Your Photos: Now, go ahead and select the rest of your horizontal, square, and other vertical photos in the order you want them to appear.
6. Preview Your Carousel: Proceed to the editor screen by tapping "Next." Swipe through your carousel. You will see that your first photo fills the frame perfectly. The other photos that don't match that aspect ratio (like your horizontal shots) will now automatically have black or white borders added by Instagram to make them fit.
7. Post as Usual: Add your caption, tags, and location, and share your post. You've successfully posted a mixed-photo carousel!

Method 2: The 'Creative Control' Method (Using a Free Design App)

Use this method when you want your carousel to look clean, professional, and on-brand. Instead of letting Instagram add generic black or white borders, this technique lets you define the border color, add subtle text, or even use patterns for the background. We'll use Canva as the example, but any free photo editing app like Adobe Express or Fotor works the same way.

Step-by-Step Instructions:

1. Decide on Your Master Aspect Ratio: First, decide which frame size you want for the entire carousel. We strongly recommend using the vertical 4:5 ratio, which corresponds to 1080 x 1350 pixels. This size takes up the most real estate on a phone screen and is optimal for engagement.
2. Create Your Canvas: Open Canva and start a new custom design. Enter the dimensions: 1080 pixels wide by 1350 pixels tall. This is your template for every slide.
3. Place Your Vertical Photos: Start with the easy ones. Upload any photos you have that are already in a 4:5 vertical format. Drop one on each page you create in your Canva project. It should fit perfectly from edge to edge.
4. Center Your Horizontal and Square Photos: Now for the others. Go to a new, blank 1080x1350 canvas in your project. Upload a horizontal (landscape) photo. Place it onto the canvas and drag it to the desired size, centering it vertically. You will see blank space above and below it. Do the same for any square photos.
5. Customize the Borders: This is where the magic happens. Click the background of the canvas (the empty space above and below your horizontal photo). You can now change its color to anything you want - a solid brand color, a simple white or gray, or an eye-catching gradient. You've effectively created custom, intentional borders.
6. Repeat for All Photos: Create a new page in Canva for every single photo in your carousel. Place each photo onto a 1080x1350 canvas and customize the background of any that don't fill the space. When you're done, you'll have a multi-page Canva project where every single page has the exact same dimensions.
7. Export and Post: Download all the pages from your Canva project as individual JPEG or PNG files. Send them to your phone. Now, open Instagram and select all your newly prepared images to create a carousel. Because they are all already the exact same size, Instagram won't crop anything or add any borders. What you designed is exactly what you see.

Pro-Tips for Making Your Mixed Carousels Stand Out

Once you've got the technique down, you can start using it to level up your content strategy.

• Lead with a Vertical Image: Always, always start your carousel with a 4:5 vertical photo if possible. This not only sets the optimal frame for your post but also ensures your carousel takes up maximum screen space, instantly grabbing more attention in the feed.
• Create Seamless Panoramas: You can embed a super-wide panoramic shot within your mixed carousel. Use an app that splits the panoramic photo into two or three perfectly cropped square or vertical slices. Position them back-to-back in the carousel to create a satisfying swipe-through effect.
• Keep Backgrounds Consistent: If you're using Method 2, don't just choose random colors for your borders. Keep them consistent throughout the carousel for a cohesive and professional look. A great approach is to use your brand's primary or secondary color, or use an eyedropper tool to pick a color directly from the photo itself.
• Mix In Videos, Too: The same principles apply to video. You can create a 1080x1350 canvas in an app like Canva and place a horizontally filmed video in the center. Export it as an MP4, and it will now be a vertical video with branded borders, ready to be placed seamlessly in your carousel alongside your photos.
• Tell a Story on Mute: Every carousel should tell a story, even without a caption. Use your sizing to create a rhythm. For example: a wide shot to establish a place, a vertical shot to introduce a person, then another wide shot that reveals some action. Guide the viewer's eye intentionally from one frame to the next.

Final Thoughts

Posting photos of different sizes on Instagram isn't complicated once you understand that the first slide dictates the frame for the rest. Whether you choose the quick in-app method or take full control with a simple design tool, you can now create more dynamic carousels that show off your photos exactly as intended.

Planning and creating visually compelling carousels like this is just one piece of the content puzzle. To keep everything organized across all your platforms - from Instagram and TikTok to Threads and YouTube Shorts - we built Postbase. We designed it as a modern, reliable hub with a visual calendar that helps you see your entire strategy at a glance, so you can spend more time creating great content and less time fighting with clunky old tools.