How do I compress a video without uploading it?

Drop the video above, choose High quality, Balanced, or Smallest file, and press Compress. FFmpeg compiled to WebAssembly re-encodes the file on your own processor, so the video is never uploaded and no server ever holds a copy of it.

How much smaller will my video get?

Phone and camera footage typically drops 50 to 80 percent on Balanced, because devices record at generous bitrates. Video that an app already compressed, such as a clip downloaded from social media, has little left to remove and may barely shrink at all.

What do the three presets actually change?

Each sets a resolution ceiling and an H.264 quality level. High quality caps at 1080p with light compression, Balanced targets 720p at the usual sharing sweet spot, and Smallest file caps at 480p with strong compression. All three output MP4 with AAC audio at 128 kbps.

Can I compress to an exact file size, like under 25 MB?

Not directly. The presets target a quality level rather than a size, which keeps quality predictable but means the final size is not. Start with Balanced, check the result, and step down to Smallest file if you are still over your limit.

Will it upscale a low-resolution video?

No. The resolution figures are ceilings, not targets, so a 480p source stays 480p on the High quality preset rather than being stretched to 1080p. Upscaling would add file size without adding any real detail.

Why is compression slow?

Video encoding is genuinely heavy work, and doing it privately in a browser tab is slower than a server farm with dedicated hardware. Expect roughly real time, so a two-minute clip takes about two minutes. Keep the tab in the foreground, because browsers throttle background tabs.

Why is there a 500 MB limit?

The encoder holds the file in browser memory, and past roughly 500 MB tabs become unstable on typical machines. For a longer recording, trim it into sections first and compress each one, or reduce the resolution before you start.

Which formats work, and what comes out?

MP4, MOV, WebM, AVI, and MKV inputs are all accepted, and the output is always MP4 with H.264 video and AAC audio, the combination that plays on essentially every phone, TV, and platform. An unusual codec in an odd container can fail; converting to MP4 first fixes it.

Video Compressor

Compress video files online free — reduce MP4 file size with quality control using FFmpeg in your browser. 100% private — runs in your browser, no server.

Files never leave your deviceInstant — no upload waitFree, no sign-up

1Choose or drop a video to compress

Choose a video or drag & drop it hereMP4, MOV, WebM… up to 500 MB · compressed on your device, never uploaded

or import from

A video compressor re-encodes a video so the file is smaller. This one runsFFmpeg compiled to WebAssembly inside your browser: pick a preset, and your video is re-encoded on your own device with no upload, no sign-up, and no watermark. Output is standard MP4 that plays everywhere.

Why a 300 MB clip will not send

Phones record at deliberately generous bitrates so footage survives editing, which is excellent for quality and hopeless for sharing. Gmail caps attachments at 25 MB, WhatsApp limits video sharing, Discord caps uploads on free accounts, and most contact forms fall over long before any of those. The usual workaround is a website that wants you to upload the file first — slow on a home connection, and a real leap of faith for footage of your family or your workplace. Re-encoding locally removes both problems at once: no upload wait, and nothing leaves the machine.

What each preset does

All three output MP4 with H.264 video and AAC audio at 128 kbps.
Preset	Resolution ceiling	Compression	Best for
High quality	1080p	Light	Archiving, keeping detail, re-editing later
Balanced	720p	Moderate	Sharing, messaging, uploads — the default
Smallest file	480p	Strong	WhatsApp, email attachments, slow connections

Those resolutions are ceilings, not targets. A 480p source stays 480p even on High quality, because upscaling would inflate the file without adding real detail. Under the hood each preset maps to a sensible H.264 quality level, so you never have to work out a bitrate.

Honest expectations

Three things are worth knowing before you start. Speed: encoding runs at roughly real time, so a two-minute clip takes about two minutes and the tab needs to stay in the foreground.Savings vary enormously: untouched phone footage usually loses 50 to 80 percent, while a video already squeezed by another app has almost nothing left to give — and in that case the tool tells you there were no savings rather than handing you a larger file and calling it compressed.Size is not a dial: the presets aim at a quality level, so if you need to land under a specific limit, compress and check, then step down a preset if you are still over.

Getting under a specific limit

Trim before compressing. Length drives size more than any setting; cutting dead footage with the video trimmer beats degrading the whole clip.
Start on Balanced, check the reported output size, and only drop to Smallest file if needed.
Drop the resolution rather than the quality if the footage will be watched on a phone.
Remove the audio with the mute tool if it is a silent screen recording — audio can be a surprising share of a short clip.
Split long recordings into parts instead of fighting the 500 MB ceiling.

ToolJiffy compared with cloud compressors and desktop encoders

	ToolJiffy	Cloud compressor	Desktop encoder
Video leaves your device	Never	Yes, uploaded	Never
Upload wait	None	Yes, plus queue	None
Free size cap	500 MB, device memory	Commonly 500 MB–1 GB	None
Watermark	Never	Sometimes on free tiers	None
Install needed	No	No	Yes
Encoding speed	Roughly real time	Faster hardware	Fastest
Exact target size	No, quality presets	Often yes	Yes

First run, and offline use

The video engine is around 31 MB of WebAssembly, fetched the first time you compress something and cached by your browser afterwards. Later sessions skip the download entirely, and once it is cached the tool keeps working without a connection — which is a fair test of the claim that nothing is being uploaded.

The rest of the video toolbox

Need only the sound? Video to MP3 extracts it. Want a short looping snippet for a chat or a bug report? Video to GIF handles that. To change format rather than size, use the video converter, and to set exact dimensions for a platform, the video resizer. Everything runs on your device.

Frequently Asked Questions

How do I compress a video without uploading it?
Drop the video above, choose High quality, Balanced, or Smallest file, and press Compress. FFmpeg compiled to WebAssembly re-encodes the file on your own processor, so the video is never uploaded and no server ever holds a copy of it.
How much smaller will my video get?
Phone and camera footage typically drops 50 to 80 percent on Balanced, because devices record at generous bitrates. Video that an app already compressed, such as a clip downloaded from social media, has little left to remove and may barely shrink at all.
What do the three presets actually change?
Each sets a resolution ceiling and an H.264 quality level. High quality caps at 1080p with light compression, Balanced targets 720p at the usual sharing sweet spot, and Smallest file caps at 480p with strong compression. All three output MP4 with AAC audio at 128 kbps.
Can I compress to an exact file size, like under 25 MB?
Not directly. The presets target a quality level rather than a size, which keeps quality predictable but means the final size is not. Start with Balanced, check the result, and step down to Smallest file if you are still over your limit.
Will it upscale a low-resolution video?
No. The resolution figures are ceilings, not targets, so a 480p source stays 480p on the High quality preset rather than being stretched to 1080p. Upscaling would add file size without adding any real detail.
Why is compression slow?
Video encoding is genuinely heavy work, and doing it privately in a browser tab is slower than a server farm with dedicated hardware. Expect roughly real time, so a two-minute clip takes about two minutes. Keep the tab in the foreground, because browsers throttle background tabs.
Why is there a 500 MB limit?
The encoder holds the file in browser memory, and past roughly 500 MB tabs become unstable on typical machines. For a longer recording, trim it into sections first and compress each one, or reduce the resolution before you start.
Which formats work, and what comes out?
MP4, MOV, WebM, AVI, and MKV inputs are all accepted, and the output is always MP4 with H.264 video and AAC audio, the combination that plays on essentially every phone, TV, and platform. An unusual codec in an odd container can fail; converting to MP4 first fixes it.