Compress Video Online to Fit Any Size Limit

xFormat compresses videos in your browser to a recommended quality or a target size such as 25 MB, working out the bitrate and resolution for you and showing the estimated size before you start, and your video is never uploaded to a server.

Runs in your browser — files never leave your device.

How it works

Got a clip that is too big to email or post? Keep the Recommended setting, or pick a size goal such as Email (25 MB) or Small (10 MB), check the estimated size, and compress. Everything happens on your own device, so there is no upload wait and no watermark.

1
Select the video you want to shrink.
2
Choose a goal (Recommended, Email ≤ 25 MB, Small ≤ 10 MB or a custom size), and optionally a resolution and output format.
3
Check the estimated size, click Compress and save the result.

How to hit a target size

File size is simply bitrate multiplied by duration. When you choose a size goal, the tool reads the video's length, subtracts the audio bitrate and keeps a 10 percent safety margin for the container and encoder variation, and uses the rest for the video. For example, 2 Mbps video plus 128 kbps audio comes to roughly 16 MB per minute of footage, so a 25 MB email limit allows about a minute and a half at that quality. If the target is too small for the video's length to look acceptable, the tool tells you and suggests trimming first.

Platform limits change, so check the current number before you pick a setting. As a rough guide, Gmail attachments top out at 25 MB, and many chat apps allow video somewhere between 10 and 100 MB.

Resolution versus bitrate

Lowering resolution and lowering bitrate both shrink a file, but they look different. On a phone screen, 720p looks nearly as sharp as 1080p, so dropping resolution is often the better first step. Cutting bitrate too far, on the other hand, brings blocky artifacts in motion and dark scenes.

That is what the Auto resolution does: when the bitrate left for the video gets low, it steps down to 720p, 480p or 360p instead of squeezing a blurry 1080p. You can also pick a resolution yourself; videos are only ever scaled down, never up. The Recommended goal keeps the original size up to 1080p and aims for about 60 percent of the original video bitrate. Audio is set to 128 kbps, or 96 or 64 kbps when the size budget is tight.

Output format and speed

Output as MP4 (H.264 and AAC) for the widest compatibility, WebM (VP9 and Opus) for the web, or MKV. Encoding uses your browser's hardware-accelerated encoders at a constant bitrate, so the result lands close to the estimate. If the browser cannot encode the format, compatibility mode (a one-time 31 MB download) uses the same bitrate with a hard cap, and writes WebM as VP8 and Vorbis. If the video is already compact, the tool warns you that it will not get much smaller.

Frequently asked questions

How do I compress a video for Discord, WhatsApp or email?

Pick Email (≤ 25 MB), Small (≤ 10 MB) or enter a custom size that matches the platform's current limit, check the estimate, then compress. Platforms change their limits, so check the number first.

Will compression ruin the quality?

Some quality loss is unavoidable, but the Recommended setting, or 720p at around 2 Mbps, usually looks good on phones and laptops.

Is my video uploaded for compression?

No. The video is compressed locally in your browser and never leaves your device.

Why didn't my video get much smaller?

If the source was already compressed at a low bitrate, there is little left to save, and the tool warns you before you start. The bitrate is never set above the original's, but try a lower resolution or a smaller target size.

What is the maximum file size?

About 500 MB on a desktop browser and about 200 MB on a phone, because of browser memory limits.