How to Change a Thumbnail on Instagram

A poorly chosen thumbnail is the social media equivalent of a great book with a terrible cover - people will just scroll past. Your Instagram thumbnail is your video's first impression, determining whether someone stops to watch or keeps on moving. This guide walks you through exactly how to change your video and Reel thumbnails on Instagram, both before and after you post, so your content can get the attention it deserves.

Why Your Instagram Thumbnail Matters More Than You Think

Before we get into the step-by-step, let's quickly touch on why this small detail has such a big impact. Your thumbnail, also known as a cover image, isn't just a placeholder, it's a powerful marketing tool for your video content.

• It's Your First Impression: On the Explore page, in hashtag feeds, and especially on your profile grid, the thumbnail is the only thing people see before deciding to click play. An engaging, clear thumbnail can drastically increase views.
• It Defines Your Grid Aesthetic: For brands, creators, and anyone trying to build a visually cohesive profile, thumbnails are everything. A consistent style in your thumbnails transforms a chaotic grid into a professional-looking portfolio that attracts followers.
• It Sets Expectations: A good thumbnail provides context. A captivating still from the video or a custom thumbnail with a text title tells viewers exactly what they're about to watch, making them more likely to tap if the topic interests them.

The Easiest Method: Choosing Your Thumbnail Before Publishing a Reel

The simplest and most flexible time to select your thumbnail is during the upload process. At this stage, you have complete control and can decide between a great frame from your video or a fully custom, branded image designed elsewhere.

Here’s how to do it step-by-step:

1. Create Your Reel as Usual

Record or upload your video clips, add your audio, text, and effects. When you're happy with your video, tap "Next" to move to the final "Share" screen where you write your caption.

2. Tap "Edit Cover"

On the Share screen, look at the preview of your Reel at the top. You'll see the text "Edit cover" overlayed on it. Tap on this preview image to open the cover selection tools.

3. Choose Your Cover Image Type

Here, Instagram gives you two options for your thumbnail:

1. Select a Frame from the Video: At the bottom of the screen, you’ll see a slider that represents your video's timeline. Drag the slider left or right to scrub through the entire video. Find a frame that is clear, well-lit, and captures the essence of your content. Avoid blurry shots or moments where you're mid-sentence with an awkward expression.
2. Upload a Custom Thumbnail: If you've created a custom image for your Reel (highly recommended for a branded look), tap "Add from Camera Roll" at the bottom. Select the image you want to use. This lets you add titles, use specific brand fonts, and maintain a uniform look for all your video content. Your custom thumbnail size should ideally be 1080x1920 pixels to fit the full 9:16 Reel format.

4. Set Your Profile Grid Crop

Once you've selected your cover image, tap "Profile grid" at the top. This is a very important step! It shows you how your vertical (9:16) thumbnail will be cropped into a square (1:1) on your main profile feed.

You can drag the image up or down to reposition the crop. Make sure the most important visual element or text from your design is centered within the square frame. This ensures your grid doesn't end up with awkwardly cropped images or cut-off text.

5. Tap "Done" and Share

After you’ve positioned your crop perfectly, tap "Done" in the top right corner. You'll be taken back to the main Share screen. Add your caption, hashtags, and then tap "Share" to publish your Reel with its beautiful new thumbnail.

How to Change an Instagram Reel Thumbnail After Posting

So, you’ve already published a Reel and just noticed the thumbnail is unflattering, blurry, or just plain wrong. Don't panic! For a while, this was impossible to fix, but Instagram now allows you to edit the cover after the fact - with one big catch.

While you can change the thumbnail, you can only select a new frame from within the video. The option to upload a custom image from your camera roll disappears after you hit publish. If you absolutely need a custom graphic thumbnail, you’ll have to use the "delete and re-upload" method described further down.

For now, here’s how to pick a better frame on a live Reel:

1. Navigate to the Reel: Go to your profile and find the Reel you want to edit.
2. Open the Menu: Tap the three dots (...) in the corner of your screen (usually top-right on iOS, bottom-right on Android).
3. Select "Edit": A menu will pop up. Choose "Edit."
4. Tap "Cover": You’ll now be in the edit screen for your Reel. On the main video preview, you should see the word "Cover" in the top-left corner. Tap it.
5. Choose a New Frame: You are now back on the "Edit cover" screen. Use the slider at the bottom to scrub through the video and find a better frame to be your new thumbnail. Notice that the "Add from Camera Roll" option is gone.
6. Adjust the Grid Crop: Just like before, tap the "Profile grid" tab to adjust the 1:1 square crop for your main profile feed.
7. Save Your Changes: Tap "Done" to confirm your new thumbnail, and then tap "Done" again to exit the edit screen. The change should take effect immediately on your grid.

Correcting Thumbnails for Regular In-Feed Video Posts

The process for standard, non-Reel video posts (the ones you share to your feed in square or landscape format) is very similar. When you're first uploading, you'll be shown options on the final share screen to select a cover, add it from your camera roll, or trim your video. You can choose your cover there.

If you need to change a live in-feed video thumbnail, the process is nearly identical to editing a live Reel's thumbnail:

1. Go to the video on your profile.
2. Tap the three dots (...) and select "Edit."
3. Tap "Cover" in the top-left of the video preview.
4. Scrub the timeline to find a new frame. Just like with Reels, you cannot upload a new custom image at this stage.
5. Tap "Done" to save.

The 'Delete and Re-Upload' Method: When All Else Fails

Let's say you've published a video that is a key part of Tuesday's content launch, and it absolutely *must* have your new custom branded thumbnail, but you forgot to add it. Since adding a new custom thumbnail to a live post isn’t possible, the only remaining option is what's sometimes called the "nuclear option": deleting the post and starting over from scratch.

Heads Up: This is a decision you shouldn't take lightly. When you delete a post, you will permanently lose all of its existing engagement - every like, comment, share, save, and view will be gone forever. The Instagram algorithm will also treat the re-uploaded video as a brand-new post.

You might consider deleting and re-uploading if:

• The post is very new and has little to no engagement yet.
• The visual consistency of your profile grid is the number one priority (e.g., you're creating a puzzle-piece feed).
• The original thumbnail was such a significant error that it's severely hindering the video's performance.

When should you absolutely NOT use this method?

• If the video has already gained a lot of strong engagement. A handful of likes is one thing, but if you have a great conversation going in the comments or the views are climbing, it’s not worth sacrificing that momentum for a better thumbnail.
• If the post is old. Deleting old-but-loved content is generally bad practice.

4 Best Practices for Standout Instagram Thumbnails

Knowing how to change a thumbnail is great, but knowing what makes a thumbnail effective is even better. Here are a few tips to make your video covers work harder for you:

1. Stay On-Brand: Consistency builds recognition. Use your brand colors, fonts, and logo (subtly!) on your custom thumbnails. If you don't use custom graphics, try to develop a consistent style - for example, always using a frame that shows you smiling at the camera.
2. Use High-Quality, Bright Images: Nobody wants to click on a dark, blurry thumbnail. Pick frames that are well-lit and in focus. For custom uploads, always start with a high-resolution file.
3. Add an Enticing Title: A short text overlay can provide powerful context. Lines like "3 Tips For...," "How I Made...," or posing a question is a great way to generate curiosity and get that click.
4. Design for the Grid Crop: Always remember that your 9:16 cover will be cropped to a 1:1 square on your feed. Keep your text and the most important parts of your image within the vertical center of your design so nothing gets chopped off. Think of it as a "safe zone."

Final Thoughts

Perfecting your Instagram thumbnail is one of the easiest ways to improve your content's performance and build a more professional-looking profile. For the most flexibility, choose your cover before you publish a Reel or video. If you need to make a correction after posting, you can easily change the cover to another frame from the video, but you won't be able to upload a new custom image unless you're willing to delete and re-upload the post.

Of course, getting your thumbnails right is just one piece of creating a cohesive social media presence. We built Postbase because managing all these details across multiple platforms can feel chaotic. With our visual content calendar, you can plan out your entire grid ahead of time, drag-and-drop posts to perfectly balance your aesthetic, and see exactly how your on-brand thumbnails will look next to each other. It helps take the guesswork out of designing a beautiful feed so you can schedule reliable posts and stay focused on what really matters - creating amazing content.