Browse Docs
Archives (14)
Audio (38)
Documents (26)
Ebooks (7)
Fonts (13)
Images (62)
Video (10)
On This Page

WEBM to MP3

Convert WebM video/audio to MP3 audio.

Try WebM to MP3 in the browser →

Convert.FAST uses this same API — what you see in the browser is what you get in code.

Quick reference

Job typevideo.webm-to-mp3
targetFormatmp3
Categoryvideo
Input formats.webm
Output extension.mp3
Costing1 credit per 5 minutes
Max file size2 GB
Max duration3000 min

Example

cURL
# 1) Submit
JOB_ID=$(curl -sS -X POST "https://api.tools.fast/convert" \
  -H "X-Fast-Api-Key: $API_KEY" \
  -F "file=@video.webm" \
  -F "targetFormat=mp3" | jq -r '.id')
# → 202 Accepted: {"id": "019e3a7b-...", "status": "Queued"}

# 2) Poll until terminal status
while true; do
  RESPONSE=$(curl -sS "https://api.tools.fast/convert/job/${JOB_ID}" \
    -H "X-Fast-Api-Key: $API_KEY")
  STATUS=$(echo "$RESPONSE" | jq -r '.status')
  [ "${STATUS}" = "Succeeded" ] && break
  [ "${STATUS}" = "Failed" ] || [ "${STATUS}" = "Canceled" ] && { echo "$RESPONSE" | jq; exit 1; }
  sleep 1
done

# 3) Download
curl -sS "https://api.tools.fast/convert/job/${JOB_ID}/download" \
  -H "X-Fast-Api-Key: $API_KEY" \
  -o "video.mp3"
# → Binary file (audio/mpeg, 6.0 MB)

Options

This converter does not support additional options.

Cost estimate

cURL
curl -sS "https://api.tools.fast/convert/estimate/webm/mp3?durationMinutes=10"
Copied.