# Cover and Thumbnail Size for Reels and Shorts

Page: https://schedulepost.fulinlabs.com/tools/cover-thumbnail-size
Last verified: 2026-11-11, against the platform documentation listed under Sources.

## Short answer

A YouTube Shorts thumbnail should be 9:16 (2160 x 3840 (9:16) recommended), at least 640 px tall, JPG or PNG, up to 2 MB on mobile or 50 MB on a computer. An Instagram Reel cover is a JPEG up to 8 MB in sRGB, 9:16 recommended; any other ratio is cropped to the middle 9:16 rectangle. A YouTube video thumbnail should be 16:9 and at least 640 px wide.

## Cover and thumbnail requirements

| Image | Format | Size | Dimensions | Notes |
| --- | --- | --- | --- | --- |
| YouTube Shorts thumbnail | JPG or PNG | 2 MB on mobile, 50 MB on desktop | Height at least 640 px; 2160 x 3840 (9:16) | Custom Shorts thumbnails can only be added in YouTube Studio on a computer, and the account must be verified. |
| YouTube video thumbnail | JPG or PNG | 2 MB on mobile, 50 MB on desktop | Width at least 640 px; 3840 x 2160 (16:9) | A regular (landscape) video. |
| Instagram Reel cover | JPG | 8 MB | 9:16 recommended | sRGB colour space. If the image is not 9:16 Instagram uses the middle 9:16 rectangle as the cover. |
| TikTok cover | A frame of the video | Not stated | The video’s own dimensions | Through the TikTok posting API the cover is a frame of the video (video_cover_timestamp_ms); the first frame is used if none is set. No separate cover image upload is documented there. |

## Frequently asked questions

### What size is a YouTube Shorts thumbnail?

YouTube Help recommends 2160 x 3840 (9:16) for Shorts, with a minimum height of 640 pixels. File size is capped at 2 MB on mobile or 50 MB on a computer, in common types such as JPG or PNG.

### Can I add a custom thumbnail to a YouTube Short?

YouTube Help says custom Shorts thumbnails can currently only be added in YouTube Studio on a computer, and that the account must be verified.

### What size is an Instagram Reel cover?

Meta's publishing reference asks for a JPEG up to 8 MB in sRGB and recommends 9:16 to avoid cropping or blank space. If the image is not 9:16, Instagram uses the middle-most 9:16 rectangle.

### Can I set a custom cover for TikTok through a scheduler?

Through the TikTok posting API the cover is a frame of the video (video_cover_timestamp_ms); the first frame is used if none is set. No separate cover image upload is documented there.

### Does SchedulePost upload a custom cover?

This page documents what each platform accepts. Check the SchedulePost composer for the cover options it offers; the tool does not assume them.

## Sources

- [YouTube Help: Add video thumbnails](https://support.google.com/youtube/answer/72431)
- [Instagram Platform: IG User Media (Reels specifications)](https://developers.facebook.com/docs/instagram-platform/instagram-graph-api/reference/ig-user/media/)
- [TikTok for Developers: Direct Post API reference](https://developers.tiktok.com/doc/content-posting-api-reference-direct-post)

The interactive checker is at https://schedulepost.fulinlabs.com/tools/cover-thumbnail-size. It runs in the browser; nothing you enter is uploaded. SchedulePost (https://schedulepost.fulinlabs.com/) schedules short-form video to TikTok, Instagram Reels, YouTube Shorts and more.