Mighty Networks native video: 4 GB for hosts, 250 MB for members

On Mighty Networks, Network Hosts can upload native videos up to 4 GB, while Space Hosts, moderators and members can upload video only as file attachments, up to 250 MB, or 25 MB if the host lowers it in Member Settings. Captions are auto-generated in English only, so a clip in another language needs captions burned in before upload.

This post covers a host's welcome clip and a member-sized clip, with Sume doing the cut and the captions.

What Mighty Networks says

Both help articles were read 2026-10-10. The numbers differ by role and by plan, so check which row applies to you.

Burn captions in for non-English members

Because Mighty does not take a caption file and supports only English captions, the way to give a Korean or Spanish audience captions is to put them in the picture. Sume's video captions takes a public HTTPS video URL, a language hint, and a style, and returns a captioned video. Standalone caption jobs cost $0.20 for videos up to 60 seconds. For a silent clip, send authored cues with text, start and end instead of relying on speech.

curl -X POST https://api.sume.com/v1/video-captions \
  -H "Authorization: Bearer $SUME_API_KEY" \
  -H "Content-Type: application/json" \
  -H "Idempotency-Key: mighty-captions-001" \
  -d '{
    "video_url": "https://example.com/welcome.mp4",
    "style": "black-outline",
    "language": "ko"
  }'

Cut a member-sized version

If your members can attach 25 MB, give them a template clip that fits. Use video trim with a short duration, drop the audio if the clip is a b-roll, and conform to a modest size and fps. Trim has no bitrate field, so check the downloaded size against 25 MB (200 megabits, counting a megabyte as 1,000,000 bytes: about 20 megabits per second for 10 seconds).

curl -X POST https://api.sume.com/v1/video-trim \
  -H "Authorization: Bearer $SUME_API_KEY" \
  -H "Content-Type: application/json" \
  -H "Idempotency-Key: mighty-trim-001" \
  -d '{
    "video_url": "https://media.sume.com/artifacts/artf_demo/clip.mp4",
    "start": 0,
    "duration": 10,
    "output": { "width": 1280, "height": 720, "fps": 24 }
  }'

Checklist

Pick the lane by role.

• Host welcome video: render once, burn captions, upload natively.
• Member prompt clip: 10 seconds or less, then measure against the 25 MB or 250 MB setting.
• Non-English audience: captions in the picture, since the platform captions are English only.
• Re-read both Mighty articles before launch.