Ultra-low latency
The fastest response time of any major avatar provider, at 471ms, about the blink of an eye. Read the technical report.
Avatar API for real-time, interactive video
LemonSlice animates any character from a single photo into a real-time avatar that listens, talks, and responds. Add the Avatar API to the stack you already use, or drop a hosted widget into your site with two lines of code.
- Ultra-low latency
- Unlimited custom avatars
- 1000+ concurrency
- 24-hr long calls
“[The avatar] is so lifelike. It is state of the art. It has been such a pleasure for us at Microsoft to work with LemonSlice.”
Brad Smith · President of MicrosoftFrom a single image to a live conversation
An avatar API lets your code create and animate a digital character. The LemonSlice Avatar API goes further and animates that character into a live, two-way conversation. Upload one photo, and go from image to a real-time video call with that character. No training, no fine-tuning, no video shoot.
Every avatar runs on a Character World Model, trained from scratch to listen, talk, and act in real time. It is a step past the deepfake and older generative technology behind traditional real-time avatars.
avatar = lemonslice.AvatarSession(
agent_image_url="https://example.com/image.png",
agent_prompt="Talk with hand gestures."
)What you can build
Put a face on the agents you already run. Anywhere you have a chatbot or voice agent, add a talking, listening avatar the same day.
Education and training
Build AI tutors, language coaches, and onboarding guides that speak and listen in real time. LemonSlice avatars make digital learning personal — boosting engagement, retention, and completion rates across any LMS or training platform.
Entertainment
Create lifelike digital characters for games, social apps, and interactive media. From AI companions to virtual streamers, LemonSlice avatars deliver real-time expression and voice that keep audiences captivated.
Physical installations
Deploy AI-powered greeters, wayfinders, and concierges on kiosks and displays in retail, hospitality, and public spaces. LemonSlice avatars turn passive screens into memorable, face-to-face customer experiences.
Business
Add a human face to customer support, sales assistants, and internal tools. LemonSlice avatars integrate with your existing chatbots and voice agents to increase trust, resolution rates, and user satisfaction.
Any character. Any style.
LemonSlice is the only interactive avatar model that can animate non-humans, like a turtle or a smiling teacup, as easily as humans.
Update a character's appearance, emotions, and actions during a live session, and swap the source image in under a second.
Built for real-time
Speed and stability are the difference between a demo and production, so the Avatar API is tuned for live conversation.
24-hour live calls
Sessions stay live for up to 24 hours without dropping, built for kiosks, installations, and always-on agents.
Live at 20 fps
Every frame is generated in real time from one photo, so replies feel like a real conversation, not a clip.
Thousands of concurrent calls
Run thousands of simultaneous avatar sessions — built for high-volume production workloads.
How interactive avatars work
LemonSlice adds a face layer on top of your voice agent. It works with any TTS and any LLM, so nothing in your stack has to change. Behind the scenes, speech-to-text and voice-activity detection listen, your LLM replies, text-to-speech generates audio, and LemonSlice turns that audio into real-time character video in a WebRTC call.
Step 1: Pick or upload any image.
Upload a photo of any character. No training, fine-tuning, or character rigs required. If it has a face, LemonSlice can animate it.
ElevenLabs v3
Sonnet 4
OpenAI Voice
Gemini Pro
Cartesia Sonic-3
GPT-5.5 Mini
Gemini Audio
Qwen3 235B
Hume
Step 2: Connect any LLM/voice model.
Plug in any language model, voice provider, and knowledge base through LemonSlice's API. OpenAI, Claude, ElevenLabs, Cartesia, and more.
Step 3: Go live with ultra-low latency.
Deploy to your site with a widget, hosted pipeline, or self-managed pipeline. LemonSlice runs at 471ms p99 latency, so conversations feel instant.
Set up an agent in 5 minutes with our developer-friendly API.
Get an API key, point LemonSlice at an image, and start a session. Call the REST endpoints to create, control, get, and list sessions, or clone the production-ready Next.js and LiveKit example to go from zero to a live avatar in an afternoon.
Choose a code example
async def my_agent(ctx: agents.JobContext):
avatar = lemonslice.AvatarSession(
agent_image_url="https://lemonslice.com/image.png",
agent_prompt="Talk with hand gestures.",
)
session = AgentSession(
stt="deepgram/nova-2",
llm="openai/gpt-5.3-chat-latest",
tts="cartesia/sonic-3",
)
await avatar.start(session, room=ctx.room)
await session.start(
)Models available for every use case
LemonSlice 2.1 is our state-of-the-art model. Available on all plans.
yourwebsite.com
LemonSlice Lite is our low-cost model for consumer interactive avatar apps
- Low cost
- Ultra-low latency
- High volumes
- Instant character creation
LemonSlice Pro is our high-res model for large-format displays and physical installations
- High resolution
- Physical installations
- Exceptional visual quality
- High-fidelity characters
Built for enterprise scale
Multi-region servers
Deploy avatar sessions from the region closest to your users for lowest latency.
Zero data retention mode
Run avatar sessions without storing conversation data — built for privacy-sensitive enterprise workflows.
Pricing
Plans start at $8/mo, and every plan includes API access. The base model runs about $0.16 per included minute. Bring your own LLM or voice model on any tier.
Learn more
