If you are evaluating real-time AI avatars for a chatbot, website or online store, you have probably come across HeyGen's LiveAvatar and similar services. They are well known, but they are not the only way to build a speaking avatar. This guide explains the two main approaches to real-time avatars, the trade-offs between them, and when a browser-rendered alternative such as Captivation AI is a better fit.
Two ways to build a real-time avatar
1. Server-streamed video. Many popular real-time avatar products, including LiveAvatar, generate the avatar's video on servers and stream it to the user's browser in real time. This approach can produce highly realistic, human-looking avatars. The trade-off is that every minute of every conversation needs server compute and video bandwidth, which affects cost at scale.
2. Browser rendering. Captivation AI uses a different approach. Pre-created visual assets are delivered to the browser and brought to life with lightweight real-time instructions from the Captivation Platform. Voice, lip sync, gestures and expressions are synchronised as the conversation happens, and the avatar is rendered on the user's own device.
How the approaches compare
| Server-streamed video | Browser-rendered (Captivation) | |
|---|---|---|
| Where the avatar is rendered | On servers, streamed as video | In the user's browser |
| Compute and bandwidth per conversation | Higher | Much lower |
| Typical running cost | Varies by provider | Around 1 to 2 cents per minute with voice |
| Realism | Often more photorealistic | Expressive, prioritises gestures and speed |
| Works with your own LLM | Varies by provider | Yes, LLM agnostic |
Captivation is open about the trade-off. Its current avatars prioritise expressive communication, gestures, speed and affordability rather than maximum photorealism. More photorealistic Captivation avatars are on the development roadmap.
When Captivation is the better alternative
Captivation is a strong choice when:
- Cost at scale matters. Browser rendering helps keep costs up to 90% lower than conventional real-time video avatar services. Captivation Inside typically costs around 1 to 2 cents per minute for an avatar with voice, roughly $0.60 to $1.20 per hour.
- You want to keep your existing AI. Captivation Inside works with your current chatbot, LLM or AI agent. Your AI writes the answers and Captivation delivers them through the avatar.
- Speed matters. The time from your AI's answer to the avatar speaking is typically 200 to 300 milliseconds when stored audio can be reused, and 600 to 800 milliseconds when new audio is generated.
- You want more than a talking head. The Captivation Media Window shows products, images, video, maps and comparisons alongside the avatar, in sync with the conversation.
- You run an online store. Captivation SuperAgents for Shopify connect to your catalogue, recommend products, add items to the basket and handle support questions.
A server-streamed service may suit you better if maximum human realism is your top priority and budget is less of a concern.
Captivation's two products
- Captivation Inside: an embeddable avatar layer for developers and AI vendors who already have a chatbot or AI agent. Plans from $100 (£75) a month, with a free developer trial.
- Captivation Solutions and SuperAgents: complete AI assistants with avatar, voice, knowledge and actions, including SuperAgents for Shopify from $65 (£49) a month, with a free trial.
Frequently asked questions
Is Captivation a good alternative to HeyGen for real-time avatars? If you need an affordable, responsive speaking avatar that works with your existing AI and runs in the browser, Captivation is a strong alternative. If photorealism is the deciding factor, compare realism side by side before you choose.
Does Captivation work on mobile? Yes. Captivation runs in modern web browsers across smartphones, tablets and PCs, with nothing for users to download.
Can I try it? Yes. There is a free Captivation Inside developer trial and a free Shopify SuperAgent trial. See pricing or contact the team.
HeyGen and LiveAvatar are trademarks of their respective owners. Captivation AI is not affiliated with HeyGen.
