How do I use the Synthesia API? | Synthesia Knowledge Base

📌 Plan availability depends on which API you use.

Interactive Avatars API: available on all plans.
Legacy (v2) API: available on Creator and Enterprise plans only.

If you'd like to upgrade your plan, please use our How do I upgrade my plan? article.

The Synthesia API lets you create personalized videos at scale from your own tools. You manage your API keys on the Developers page in Synthesia Studio, where you can create a key, set its scope and expiration, and disable or delete it.

How do I create an API key?

Select Developers in the sidebar.
Select the API keys tab, then select New API key.
Enter a Name for the key.
Choose a Scope (see below).
Choose when the key Expires: 7 days, 30 days, 90 days, 1 year, or never. The default is 30 days.
Select Create API key.

✍️ Your API key is shown in full only once, when you create it. Copy it and store it somewhere safe, because you can't view it again. If you lose a key, create a new one. Treat your API key like a password, and avoid sharing it outside your own integrations.

API key scopes

Each API key works with one API surface. Choose the scope that matches the API you're calling.

Interactive Avatars — works with developers.synthesia.io/api
Legacy (v2) — works with api.synthesia.io/v2

A Legacy (v2) key won't authenticate against developers.synthesia.io/api, and an Interactive Avatars key won't authenticate against api.synthesia.io/v2.

Managing your keys

The API keys tab lists every key on your account, including its name, a masked key, scope, expiration, status, and creation date. Search by name to find a specific key.

To manage a key, select the more options menu (⋯) next to it. You can:

Select Edit key to change the key's name, scope, or expiration, and copy its Key ID for support requests.
Select Disable / Enable to deactivate a key, or reactivate a disabled one, without deleting it.
Select Delete to remove the key. A deleted key can't be recovered.

Using the API

See the dedicated Synthesia API documentation to learn how to use Synthesia APIs.

💡 If you're using the Synthesia API for the first time, follow the API QuickStart guide to get started.

💬 FAQs

Which plans include API access?

API access depends on the API you use. The Interactive Avatars API is available on all plans. The Legacy (v2) API is available on Creator and Enterprise plans. If you want to use the Legacy (v2) API and you're on a different plan, contact the Synthesia Support team about upgrading.

Can I view my API key again after creating it?

No. Your API key is shown in full only when you create it. If you can't find your key, create a new one on the Developers page and update your integration with the new key.

What happens when my API key expires?

An expired key stops authenticating requests. Create a new key on the Developers page and update your integration with it. To reduce interruptions, choose a longer expiration when you create a key.

Which scope should I choose?

Choose Interactive Avatars for the developers.synthesia.io/api surface, or Legacy (v2) for the api.synthesia.io/v2 surface. Each key works with one surface only.

📚 To manage your keys and credits, visit Developers – Synthesia Docs.

To make your first API call, follow the Video API Quickstart.