Convert MP4 to WebM via API

WebM is the open, royalty-free format preferred by browsers. Convert your MP4 files to WebM with a single API call using VP8 or VP9 encoding.

Try it in your browser

Loading FFmpeg engine... (~31 MB)

Use the API

curl -X POST https://renderio.dev/v1/commands \
  -H "X-API-KEY: ffsk_your_api_key" \
  -H "Content-Type: application/json" \
  -d '{
  "ffmpeg_command": "-i {in_video} -c:v libvpx -crf 30 -b:v 0 {out_video}",
  "input_files": {
    "in_video": "https://example.com/input.mp4"
  },
  "output_files": {
    "out_video": "output.webm"
  }
}'

Need an API key? Get your free API key to start processing files programmatically.

Common Variations

VP9 encoding for better compression

-i input.mp4 -c:v libvpx-vp9 -crf 31 -b:v 0 output.webm

With Opus audio codec

-i input.mp4 -c:v libvpx-vp9 -crf 30 -b:v 0 -c:a libopus output.webm

Two-pass encoding for target bitrate

-i input.mp4 -c:v libvpx-vp9 -b:v 2M -pass 1 -f null /dev/null && -i input.mp4 -c:v libvpx-vp9 -b:v 2M -pass 2 output.webm

Low quality for fast preview

-i input.mp4 -c:v libvpx -crf 40 -b:v 0 -s 640x360 output.webm

Related Operations

Convert WebM to MP4 via API | RenderIO Convert MP4 to MOV via API | RenderIO Compress Video via API | RenderIO Convert MP4 to VP9 via API | RenderIO

Need to process at scale?

Automate this with the RenderIO FFmpeg API. Process thousands of files programmatically or through no-code video automation.

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