LemonSlice vs Tavus: which one is better?

Both platforms support photorealistic human avatars suitable for conversational video agents.

Both LemonSlice and Tavus allow you to trigger specific emotions during a conversation using a tool call. This feature is available to Enterprise customers only.

Tavus can only do humans. Tavus does not support animals, fantastical creators, or objects with faces. Stylized or cartoon humans are also frequently rejected by the platform.

LemonSlice supports any character in any style, from cartoons to animals to drawings and more

LemonSlice avatars have dynamic hand gestures that are synchronized to the spoken audio. The more expressive the audio, the more expressive the hand gestures will be.

Tavus does not support dynamic hand gestures. It will error out if you try to pass in an image with hands.

LemonSlice also allows you to update the video midway through a conversation by passing in a new image. Using this technique you can update the avatar’s clothing or scene in real-time, which can be powerful for eCommerce or storytelling applications.

Tavus does not support this.

In addition to natural hand gestures, LemonSlice also allows users to trigger specific gestures or whole-body actions. These actions could be anything like waving, cheering, or jumping. Actions must be specifically onboarded for each character. This feature is available to Enterprise customers for an additional fee.

Tavus does not offer triggerable hand gestures or whole body motions.

LemonSlice avatars are created instantly from a single photo. There is no training required - just pass an image URL to the API and immediately allow your users to chat with it. You can create unlimited avatars on any LemonSlice subscription. You only pay for minutes of usage.

Tavus trains a custom model per avatar, which takes 2-6 hrs and costs $40-$65 per avatar. A certain number of custom avatars are included each month with your subscription.

LemonSlice avatars cost $0.1367/min of avatar-only conversation on the highest tier Self-Serve plan. And $0.2133/min for the entire pipeline (STT, LLM, TTS, etc).

Tavus avatars cost $0.32/min on the highest tier Self-Serve plan for the entire pipeline (STT, LLM, TTS). We do not know the avatar-only price per minute for Tavus.

LemonSlice Flash has significantly faster response times than Tavus Phoenix-4 at every percentile from p50 to p99. For real-time applications, p75 and p99 often matter more than p50.

Read the technical report here

Both Tavus and LemonSlice have robust integrations with WebRTC platforms like Daily/Pipecat and LiveKit. LemonSlice also has an Agora integration. These integrations allows you to build avatars into your product.

Tavus avatars are at 1080p resolution. LemonSlice avatars are typically at 512px resolution, but high-res (Pro model) is available for customers on Enterprise plans. High-res LemonSlice avatars are used in situations where an avatar needs to be life-sized on a big screen.

Many of the differences in model capabilities stem from the different technical approaches each company has taken. Therefore, here is a mental model of the two technologies.

LemonSlice - an end-to-end video diffusion transformer (DiT) model. This is the same type of model as Veo3 or Sora, except running in real-time on a single GPU. It is the most advanced type of video model in the field of AI video today.

We cannot be 100% sure of Tavus’ technical approach but if we had to guess:

Earlier Phoenix Models - use looping, pre-recorded footage with lip-sync. The lip-sync model is trained per character and requires ~2min of video footage. This approach can only support photorealistic humans. Furthermore, it is always a bit uncanny because the hand gestures and facial expressions do not match what’s being said. This approach works for neutral, understated speaking but breaks down for more expressive performances because the looping becomes more obvious. This approach supports moving backgrounds (trees swaying, etc) because it’s a looping, real-world video but care must be taken not to have motions that cannot be reversed (like a person walking backwards, etc).

Phoenix-4 - Tavus’ newest model is likely a two-stage model pipeline: audio → keypoints/gaussian splat → RGB pixels. This approach cannot support non-human characters (like animals) or hand gestures due to the limitations of the intermediate representation. The Gaussian splat approach leads to a slight “bobble head” effect where the face gets slightly bigger and smaller as the avatar talks.

A custom model must be trained per character, which requires 1min of video footage. Tavus has the option to create an avatar from a single image. We believe they do this by generating video footage using a different video model and then using that footage to train their interactive model.

Since Phoenix-4 is Tavus’ latest model, all comparisons on the page are done using only this model version.