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Free Online Tool

Change Your Video Cover Instantly

Upload your video file and a new cover image, combine them together in your browser, and download the result. Works on iPhone, Android, PC, Mac, and every device.

100% in-browser No file uploads No sign-up needed

Trusted by content creators, video editors, and social media managers worldwide. Free, private, and works on all devices.

Cover Changer

Drop your video and a new cover image below. We will combine them for you.

Drop video file .mp4 .avi .mkv .mov .mpeg .rm .rmvb .vob .webm .wmv
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Replace
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Drop cover image .png .jpg .jpeg .webp .gif .bmp .tiff .heic .heif
Cover preview
Replace
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WORKS EVERYWHERE

Change Video Cover on Any Device

No matter which device or platform you use, Video Cover Changer works directly in your browser — no extra software required.

iOS

iPhone & iPad

Change video cover on iPhone or iPad using Safari, Chrome, or any mobile browser. The new video downloads straight to your Files app, ready to use.

ANDROID

Android

Change video cover on any Android phone or tablet. Works with any video player app.

DESKTOP

Windows, Mac & Linux

Change video cover on any desktop OS. Works with VLC, QuickTime, Windows Media Player, and more.

Unlike desktop video editors or online converters, Video Cover Changer runs entirely in your browser — no installation, no uploads, no account needed.

HOW IT WORKS

Three Steps to a New Cover

Upload

Drag and drop your video file and the new cover image into the two slots. Everything stays in your browser.

Change

Click the change button and watch your files combine. Processing takes just seconds.

Download

Your new video with the replaced cover is ready. Download instantly — no sign-up, no watermark, no limits.

WHY CHOOSE US

Why Video Cover Changer Is Different

Not all video cover tools are the same. Here is what makes this tool unique.

100% Client-Side Processing

Your files never leave your device. Unlike other tools that upload your video to a server, Video Cover Changer runs entirely in your browser using JavaScript and FFmpeg.wasm. Your content stays private — always.

No Sign-Up, No Watermark, No Ads

Many free video tools require an account, add watermarks to your output, or bombard you with ads. Video Cover Changer has none of that — just a clean, fast tool that works.

Works on Every Device

Whether you are on iPhone, Android, Windows, Mac, or Linux, the tool works the same way. No app installation, no video editor setup, no plugins — just your browser.

Preserves Video Quality

When you change the cover, the original video stream, audio stream, and all metadata remain intact. Only the cover/thumbnail image is replaced.

Supports 10+ Video Formats

MP4, AVI, MKV, MOV, MPEG, RM, RMVB, VOB, WebM, WMV, FLV, 3GP, M4V — drag and drop any common video format. The tool handles the conversion automatically.

Smart Device Adaptation

The tool automatically detects your device's memory and adjusts file size limits accordingly — up to 2 GB for videos and 100 MB for images on high-end devices.

UNDER THE HOOD

How Video Cover Replacement Works

Understanding the technical process helps you trust the tool and troubleshoot any issues. Here is exactly what happens when you click the Change Cover button.

1

Video Validation

The file is checked to ensure it is a valid video file by examining its magic bytes and file signature. The file size is also validated against device memory limits — up to 2 GB on high-end devices.

2

FFmpeg.wasm Initialization

The tool loads FFmpeg.wasm, a WebAssembly port of the powerful FFmpeg multimedia framework. This enables full video processing capabilities directly in your browser without server-side processing.

3

Image Decoding & Format Conversion

The new cover image is decoded from its binary format. Non-standard formats like HEIC, HEIF, TIFF, and BMP are converted to JPEG using the Canvas API. PNG and JPEG images are processed directly without conversion.

4

Cover Embedding with FFmpeg

FFmpeg embeds the new cover image as the video's poster frame/thumbnail. The cover is encoded and attached to the video container's metadata stream, replacing any existing cover art.

5

Stream Copy (No Re-encoding)

The video and audio streams are copied directly without re-encoding using FFmpeg's -c copy flag. This preserves the original quality and ensures fast processing — only the cover metadata is modified.

6

Video Serialization & Download

The modified video is serialized back into a valid video file with the new cover embedded. The resulting Blob is offered as a download with the original filename and _changed suffix.

FAQ

Frequently Asked Questions

What video formats are supported?
Upload MP4, AVI, MKV, MOV, MPEG, RM, RMVB, VOB, WebM, WMV, FLV, 3GP, M4V video files and PNG, JPG, JPEG, WebP, GIF, BMP, TIFF, HEIC, or HEIF cover images. The new image replaces the existing cover/thumbnail while preserving all video and audio content.
Is there a file size limit?
Video files up to 500 MB-2 GB and cover images up to 10-100 MB (adjusted based on your device memory). All processing happens locally in your browser, so speed depends on your device.
Are my files uploaded anywhere?
No. Video Cover Changer processes everything client-side using JavaScript and FFmpeg.wasm. Your videos and images never leave your device — complete privacy by design.
What image dimensions should I use?
Most video platforms display covers at 1280 x 720 pixels (16:9 ratio) or 1920 x 1080 pixels. Use that resolution or higher for the best results across YouTube, Vimeo, and other platforms.
How to change video cover on iPhone?
Open this page in Safari or Chrome on your iPhone. Tap the left slot to choose your video file from the Files app, tap the right slot to pick your new cover image from Photos, then tap Change. The new video downloads to your Files app.
Can I change YouTube video thumbnail?
Yes. Change the video cover using this tool, then upload the updated video to YouTube. Note that YouTube also allows custom thumbnails directly in YouTube Studio without re-uploading.
Does it re-encode my video?
No. Video Cover Changer uses FFmpeg's stream copy mode to avoid re-encoding. Your original video and audio quality is preserved — only the cover/thumbnail metadata is modified.
What is the best free video cover changer?
Video Cover Changer is a free, privacy-first video cover changer that works entirely in your browser. No file uploads to servers, no sign-up, no watermark, no ads. Supports MP4, AVI, MKV, MOV, WebM, WMV and more.
Can I change video cover on Android?
Yes. Open Video Cover Changer in Chrome, Firefox, or any browser on your Android phone or tablet. Select your video file and new cover image, then tap Change. The new video downloads to your device.
Is Video Cover Changer safe to use?
Absolutely. Video Cover Changer processes all files locally in your browser using WebAssembly technology. No files are uploaded to any server, ensuring complete privacy and security. The tool is open-source and uses the trusted FFmpeg.wasm library.
How long does it take to change a video cover?
Processing typically takes just a few seconds to a minute, depending on your device's performance and the video file size. Since the tool uses stream copy mode (no re-encoding), it's much faster than traditional video editors.
What is FFmpeg.wasm and why does this tool use it?
FFmpeg.wasm is a WebAssembly port of FFmpeg, the industry-standard multimedia framework. Video Cover Changer uses it to process videos entirely in your browser without server uploads, ensuring privacy, speed, and zero cost.

Ready to Change Your Video Cover?

Free. No sign-up. Works on iPhone, Android, Windows, Mac, and every device.

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