Compress video

Presets for WhatsApp or email, plus an advanced CRF mode

No database: AIMRAN doesn't store your files, text or results

What is Compress video?

This tool reduces the size of a video so you can send it on WhatsApp, attach it to an email or store it using less space. You pick a compression level and the tool tells you roughly how big the file will be before you start.

If you want to keep it simple, use the High, Medium, Low, WhatsApp or Email buttons. If you know what you are doing, advanced mode lets you adjust the resolution, quality, frames per second and audio.

How to use it

Drag your video into the upload area or click to choose it.
Pick a preset: High, Medium, Low, WhatsApp or Email.
For more control, turn on advanced mode and adjust resolution, CRF or bitrate, fps and audio.
Check the estimated size and click Compress video.
Download the resulting MP4 and check the percentage saved.

Advantages

Presets designed for WhatsApp (720p and under 16 MB) and email (under 25 MB).
Estimated final size and output resolution before processing.
Advanced mode with CRF from 18 to 40 or a fixed bitrate from 200 to 8,000 kb/s.
Free, no sign-up and no watermarks on the video.

Technical details

Output is always MP4 with H.264 video (libx264, veryfast preset, yuv420p) and AAC audio, with the moov atom at the start (+faststart) for instant playback. The High, Medium and Low presets use CRF 23, 28 and 32 (Low limits the short side to 720 px). WhatsApp and Email work by target size (15.5 MB and 24 MB): the video bitrate is calculated from the duration, minus the audio and a 7% container margin, with maxrate of 1.4x and bufsize of 2x; if the resulting bitrate drops below 80 kb/s you are warned that the quality would be unacceptable. In advanced mode you can scale to 1080p, 720p, 480p or 360p, set 60, 30, 24 or 15 fps, choose AAC audio from 64 to 192 kb/s or remove it. The CRF estimate is approximate (bits-per-pixel model). Accepts MP4, MOV, WEBM, MKV, AVI, 3GP, FLV, TS, WMV and others, up to 500 MB per file.

Frequently asked questions

How do I compress a video to send on WhatsApp?

Upload the video, choose the WhatsApp preset and click Compress video. It is scaled down to 720p and the bitrate is adjusted so the file stays under 16 MB.

Does compressing a video reduce its quality?

There is always some loss because it is re-encoded, but with the High preset (CRF 23) the difference is barely noticeable. The lower the CRF, the higher the quality and the larger the file.

What is CRF?

It is H.264's constant quality mode: the encoder uses as many bits as it needs to keep the quality even. 23 is the standard; higher values reduce the size at the cost of quality.

Why does it say my video is too long for that size?

With the size-based presets, a very long video would have to be encoded at very few kb/s. Trim it first or use a quality-based preset such as Medium or Low.

What format is the compressed video downloaded in?

MP4 with H.264 and AAC, the most compatible format for phones, computers, social media and email.