How to compress MP4 files
Upload your MP4 file
Drag and drop a file or click to select one. Keep this page open while the file uploads and converts.
Compress the file
NexMedia re-encodes your MP4 file on its own servers at the quality you choose. Processing time depends on the file size and how busy the queue is.
Download the compressed file
When the compression finishes, the download appears on this page. Your compressed file is kept for 2 hours, then deleted.
About MP4
the universal video container, usually holding H.264 video and AAC audio
MP4 (MPEG-4 Part 14) is the most widely supported video container in existence: phones, browsers, smart TVs and every major video site play it. It usually holds H.264 or H.265 video with AAC audio, and it can also carry subtitles and chapter markers.
MP4 files get large because video eats bitrate: a 1080p recording at a typical 8 Mbps already stores about 3.6 GB per hour, and phone cameras often record at two or three times that rate.
What compressing MP4 does
Compressing an MP4 re-encodes it into a more efficient container and codec: WebM's VP9 holds the same picture in noticeably fewer bytes than the H.264 almost every MP4 carries.
A 10-minute 1080p MP4 at 8 Mbps weighs roughly 600 MB; the same clip re-encoded to WebM at a quality-matched bitrate is often 40–60% smaller.
Settings you can change
Before you compress MP4, you can adjust: Video codec, Rate control, Quality (CRF), Video bitrate, Resolution, Width, Height, Scale fit, Frame rate, Encoder preset, Audio codec, Audio bitrate, Trim start, Trim duration, and Remove metadata.
Limits
Guests can compress files up to 100 megabytes and run 5 conversions per day; a free account raises this to 500 megabytes and 25 per day; paid plans go up to 100 gigabytes.
Your compressed MP4 file is kept for 2 hours, then deleted.
Compressing MP4: questions and answers
Will compressing MP4 reduce quality?
Some quality loss is unavoidable when re-encoding H.264 video, but at a sensible bitrate the difference is hard to see, and the resolution and frame rate can be kept identical.
Can MP4 files be compressed without any loss?
No. MP4 video is already lossy (H.264 or H.265), so a second encode cannot be lossless — the win is that a modern codec reaches the same perceived quality at a much lower bitrate.
Which settings can I change when compressing MP4?
You can adjust: Video codec, Rate control, Quality (CRF), Video bitrate, Resolution, Width, Height, Scale fit, Frame rate, Encoder preset, Audio codec, Audio bitrate, Trim start, Trim duration, and Remove metadata. the quality slider trades bitrate for file size, and dropping the resolution (1080p to 720p, say) roughly halves the bitrate a clip needs
How much smaller will my MP4 file get?
Most MP4s shrink by a third to a half when re-encoded to WebM at matched quality; lowering the resolution or the frame rate saves more.
How large a MP4 file can I compress for free?
Guests can compress files up to 100 megabytes and run 5 conversions per day; a free account raises this to 500 megabytes and 25 per day; paid plans go up to 100 gigabytes. Your compressed file is kept for 2 hours, then deleted.