Synthesia Pro has 5 personal avatars; Sume avatars are handles

Synthesia's pricing page lists 5 personal avatars on the Pro plan and unlimited personal avatars on Enterprise. Sume has no slot count in its docs: an avatar is a reusable resource created by POST /v1/avatar-1.0/generate from a prompt, a profile or a reference image, and you refer to it by a handle in later talking-video calls. For a team with several brands, that changes the question from how many slots to how to name and organise handles.

Synthesia source: pricing, read 2026-10-04. Sume sources: Create new avatar and Generate avatar video.

What the plan limit means on each side

On Synthesia the count is a plan feature, so a sixth personal avatar on Pro means looking at a different plan; the page lists unlimited personal avatars only on Enterprise. On Sume the docs describe the avatar as a job-backed resource in your workspace and do not state a cap, and this post does not invent one. Check your account limits and the pricing for avatar creation before you commit to a large roster.

Naming a roster

The handle is the stable key your code uses, so choose it like a database id. A leading @ is accepted but stored without it. Keep one handle per face and per brand voice, and avoid encoding a campaign into the name, because the same face will serve several campaigns.

• brand_host for the main presenter.
• brand_host_alt for a second look.
• Put the date or campaign in your own table, not in the handle.

The workflow after creation

Create the avatar once, poll the job to completed, then call the talking-video route with avatar_handle. The video docs call for a ready avatar, so store the avatar job and gate video submits on it.

curl -X POST https://api.sume.com/v1/avatar-1.0/generate \
  -H "Authorization: Bearer $SUME_API_KEY" \
  -H "Content-Type: application/json" \
  -H "Idempotency-Key: avatar-brand-host-001" \
  -d '{"avatar_handle":"brand_host","input":{"type":"props","ethnicity":"Asian","sex":"female","age":28}}'

Bottom line

If you want exactly five named presenters and a hosted editor, Synthesia Pro is a clear package. If you want to create avatars programmatically and refer to them by handle in a pipeline, Sume's model fits better. Either way, record who may use which face; a real person behind a photo avatar must have agreed.