Seeduplex
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Try Seeduplex Free

Experience full-duplex voice AI — speak and listen simultaneously, just like a real phone call. Three ways to get started:

Doubao App

Recommended

The official way to experience Seeduplex. Download Doubao (ByteDance's AI app) and start a voice conversation — full-duplex is enabled by default.

  1. 1Download Doubao from App Store or Google Play
  2. 2Create a free account (no credit card needed)
  3. 3Tap the voice icon → select "Voice Call" mode
  4. 4Start talking naturally — Seeduplex handles the rest
Open Doubao →

Doubao Web

Browser

Use Seeduplex directly in your browser at doubao.com. Works on Chrome, Safari, and Firefox with microphone permissions.

  1. 1Go to doubao.com
  2. 2Log in or create a free account
  3. 3Click the microphone icon in the chat
  4. 4Allow microphone access when prompted
Open Doubao Web →

Seed API

Developer

Integrate Seeduplex into your own application via the Seed API. Free tier includes 100 minutes/month. API access is rolling out — apply for early access.

  1. 1Apply for Seed API access at seed.bytedance.com
  2. 2Install the SDK: npm install @bytedance/seed-sdk
  3. 3Initialize a full-duplex voice session
  4. 4Stream audio bidirectionally in real-time
View API Docs →

What to Expect

First 10 seconds

You'll notice the AI doesn't wait for silence to start responding. It starts forming answers while you're still speaking.

Try interrupting

Cut in mid-sentence. Seeduplex handles it gracefully — acknowledges the interruption and adjusts, like a person would.

Test noisy environments

Try talking with background music or TV on. The semantic noise suppression filters it surprisingly well.

Natural pauses

Pause mid-thought. The AI waits rather than jumping in — it can tell you're thinking, not finished.

seeduplex.io is an independent resource and is not affiliated with ByteDance. Seeduplex™ is a trademark of ByteDance Ltd. Voice access is provided via the official Doubao platform.