When you receive a finished video from your editor, the image that appears before someone presses play (the thumbnail) is determined by the platform where you post the video, not by the video file itself. Every platform (LinkedIn, YouTube, your website, etc.) automatically pulls a frame from the video to use as the default thumbnail. If you want a specific image to appear instead, you'll need to set a custom thumbnail on that platform.
Key Concepts
A video file does not contain a separate thumbnail image. When you upload a video to any platform, that platform picks a frame from the video and displays it as the preview image. This is true of YouTube, LinkedIn, Facebook, and most other publishing destinations.
If you want a specific frame to show as the thumbnail, like a title screen or a branded intro card, you'll need to capture that frame yourself and upload it as a custom thumbnail on the platform where you're posting. This is a standard step in the publishing process for any video, on any platform.
How to Capture and Set a Custom Thumbnail
The process takes about 30 seconds once you know which frame you want. Here's how to do it on any device.
Find the frame you want
Open your finished video in the MarketScale Studio proofing room or any video player. Scrub through the video until you land on the exact frame you want to use as your thumbnail.
Take a screenshot
Capture a screenshot of the frame.
Pro tip: Most operating systems have integrated keyboard shortcuts to take quick screengrabs and save the file locally:
Mac: Command + Shift + 4 and drag to select the video frame.
Windows: Windows + Shift + S and select the area.
Upload the thumbnail on your publishing platform
When you upload or publish your video on the destination platform, look for the thumbnail or cover image option. Most platforms let you upload a custom image during or after the upload process. Select the screenshot you just saved.
Platform-Specific Tips
YouTube: After uploading, click on the video in YouTube Studio and look for the Thumbnail section. Click "Upload thumbnail" and select your image. Recommended size is 1280 x 720 pixels.
LinkedIn: When sharing a video post, LinkedIn lets you pick a frame from the video or upload a custom thumbnail. Look for the pencil/edit icon on the video preview before posting. Recommended size is 1200 x 627 pixels.
Facebook: After uploading a video, click "Edit" on the post and look for the thumbnail option. You can choose from auto-generated frames or upload your own. Recommended size is 1200 x 675 pixels.
Your website or blog: Most CMS platforms (WordPress, HubSpot, etc.) let you set a featured image or poster frame for embedded videos. Check your platform's documentation for the exact steps.
Best Practices
These habits will help your thumbnails look intentional across every platform:
If you plan to post the same video on multiple platforms, capture the screenshot once and resize it as needed for each destination.
Title cards and branded intro frames make strong thumbnails because they immediately tell viewers what the video is about.
Avoid using a frame where the speaker is mid-sentence or blinking. Pause on a clean, composed moment.
If you want a more polished thumbnail with text overlays or branding, free tools like Canva offer templates pre-sized for YouTube, LinkedIn, and other platforms.
FAQs
Common questions about thumbnails and how they work with your edited videos.
Can my editor set the thumbnail for me?
No. Your editor delivers the video file, but the thumbnail is set at the point of publishing, which is controlled by the platform you post to.
Why does the video show a random frame before I press play?
Every platform auto-selects a frame from the video as a default thumbnail. You can override it by uploading a custom thumbnail image on that platform.
What size should my thumbnail image be?
It depends on the platform. YouTube recommends 1280 x 720 pixels. LinkedIn works best at 1200 x 627. When in doubt, capture a wide screenshot and crop to fit.