Media uploads

Images and videos used in profiles (avatar, banner), live stream covers, clips, and product photos need to be available on Nostr as URLs. To get a URL from a file, upload it to a media hosting service.

If users don’t have their own media hosting, they can use nostr.build  — a NIP-96 file storage service. All uploads to nostr.build require NIP-98 authentication.

Upload flow

1. Discover the upload endpoint:

curl https://nostr.build/.well-known/nostr-basics/nip96.json

2. Upload with NIP-98 auth:

AUTH=$(nak event -k 27235 \
  -t u=https://nostr.build/api/v2/nip96/upload \
  -t method=POST \
  --sec <nsec1...> < /dev/null 2>/dev/null | base64)
 
curl -X POST \
  -H "Authorization: Nostr $AUTH" \
  -F "file=@image.jpg" \
  https://nostr.build/api/v2/nip96/upload

The response contains a nip94_event with tags including the hosted URL. Use that URL in:

• Profile picture / banner fields (Profile and relays)
• Stream image tags (Live event structure)
• Clip imeta tags (Clips)
• Product image tags (Products)

Related

• NIP-98 HTTP authentication