Millis AI
Low-latency voice-agent platform with a $0.02/min platform fee on top of separately priced STT, LLM and character-metered TTS; bring your own LLM endpoint at no LLM charge.
Overview
Best for: Cost-sensitive builders who want a cheap orchestration fee and their own LLM.
At a glance
$0.02/min platform fee plus STT, LLM and per-character TTS; phone minutes from your own carrier. Pricing page looks stale.
Web SDK and phone (via your Twilio/Plivo etc.)
Same
Not verified.
Vendor markets very low latency; no verified number.
Not verified.
Not verified.
Features
- multi-provider plug-ins
- custom LLM endpoint
- telephony integrations
- 'Choose by Millis' lowest-latency model selection
Pricing
| What | Price | Unit |
|---|---|---|
| Platform fee | $0.02 | per minute |
| STT | $0.0043 | per minute |
| LLM | GPT-4o ~$0.004, GPT-3.5 Turbo ~$0.0004, Llama-3 ~$0.00018 | per minute (estimate) |
| TTS | ElevenLabs $0.10, Cartesia $0.0392, OpenAI/Deepgram $0.015, Rime $0.075 | per 1,000 characters |
$0.02 + $0.0043 STT + ~$0.004 LLM + $0.0075-$0.05 TTS + your carrier minutes (~$0.005-$0.014). Third-party worked example: ~$0.066/min with GPT-4o + ElevenLabs.
Free tier: Not published.
Source: docs.millis.ai
Setup
- Sign up and create an agent (prompt, voice, LLM) in the dashboard.
- Use the web SDK for browser calls or connect a Twilio/Plivo number for phone.
- Optionally point the agent at your own LLM endpoint.
Endpoint
Millis APIAuthentication
Public key (web SDK) / private API key
Quick start javascript
// Millis agents are created in the dashboard; see docs.millis.ai for the current web SDK snippet.
// Snippet not reproduced here because the SDK surface could not be verified on 2026-10-10.Written from the current docs. Check the vendor's SDK version before you ship.
Warnings
TTS billed per character
Cost depends on how much the agent talks; a chatty agent with ElevenLabs costs several times the headline.
Pricing page looks stale
Docs still list GPT-4 Turbo, GPT-3.5 and PlayHT; confirm current models and rates in the dashboard.
Telephony not priced
Phone minutes come from your own carrier account.
Limited public compliance info
No SOC 2/HIPAA statements were verified.
Plus 12 warnings that apply to all platforms and telephony APIs. See category warnings.
Limits
- Concurrency not published
Models and products
| Name | Status |
|---|---|
| Pay as you go | GA |
Docs and sources
Docs
Sources used
Whether model/TTS list is current; concurrency; free credit; SDK snippet.