How to compress WebM files
Upload your WebM 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 WebM 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 WebM
the open web video container, usually holding VP8 or VP9 video
WebM is the open container built for the web: it holds VP8, VP9 or AV1 video with Vorbis or Opus audio, and every major browser plays it without plugins.
WebM grows with bitrate and length like any video, but VP9 already compresses efficiently, so an oversized WebM usually means the encoder ran at a needlessly high quality target or the source was very long.
What compressing WebM does
Compressing a WebM re-encodes it with a tighter bitrate budget: VP9 video responds well to a second pass, often keeping its quality while dropping well below its first encoding's size.
A 10-minute 1080p VP9 clip can sit near 250 MB at a generous bitrate; the same clip at a tuned quality target is frequently half that.
Settings you can change
Before you compress WebM, 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 WebM file is kept for 2 hours, then deleted.
Compressing WebM: questions and answers
Will compressing WebM reduce quality?
A re-encode of already-efficient VP9 costs less quality than an H.264 re-encode at the same size, because VP9's rate control spends the bits where the eye looks.
Can WebM files be compressed without any loss?
Practically no. VP8 and VP9 encodes are lossy by design (VP9 has a lossless mode that almost no tooling targets), so compression here means equal perceived quality at fewer bytes.
Which settings can I change when compressing WebM?
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 sets VP9's constant-quality target, and capping the resolution keeps long screen recordings from ballooning
How much smaller will my WebM file get?
A high-bitrate WebM typically drops by a quarter to a half at a tuned quality target, with the picture staying watchably identical.
How large a WebM 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.