Speech · backend

Use AssemblyAI Universal 2 with FastAPI

Updated 2026-05-21 · By XALEN

How to use AssemblyAI Universal 2 (Speech, ~2B) with FastAPI. Install, authenticate, and make your first API call in minutes. Working code example included.

Model

AssemblyAI Universal 2

~2B · Long-form context · $0.006/min input

Framework

FastAPI

backend · pip install xalen fastapi uvicorn

1. Install

pip install xalen fastapi uvicorn

2. Code

from fastapi import FastAPI
from pydantic import BaseModel
from xalen import XALEN

app = FastAPI()
client = XALEN(api_key="xln_test_YOUR_KEY")

class ChatRequest(BaseModel):
    messages: list

@app.post("/chat")
async def chat(req: ChatRequest):
    response = client.chat.completions.create(
        model="assembly-ai-universal-2",
        messages=[m.dict() for m in req.messages]
    )
    return {"reply": response.choices[0].message.content}

AssemblyAI Universal 2 with Other Frameworks

Python JavaScript Flask cURL

Other Models with FastAPI

Vedika Standard Vedika Fast Vedika Pro Ultra Vedika Vision Vedika Code Vedika Pandit Voice

200+ models. One API. Works with any framework.

Get API Key

Last updated: 2026-05-21